Search engine marketing (SEM) accounts for roughly three out of every eight dollars spent on digital advertising, with Google alone commanding 31% of the market.

That share is even larger within the b2b marketing space, and for good reasons: 88% of b2b buyers conduct online research before making business purchasing decisions, and nearly half of b2b tech buyers say they’ve discovered brands they weren’t previously aware of through a search engine.

While organic search traffic still drives roughly half of business website traffic, paid search accounts for 10%—and it enables marketers to guarantee first-page presence even for highly competitive search phrases that are difficult to optimize for organically.

So how can search engine marketers maximize their click-through rate (CTR) and conversions from paid search? Which tools and reports are most helpful? How and when should marketers use retargeting and ad extensions? What common SEO pitfalls and mistakes should they avoid?

Find the answers to those questions and many others here in more than two dozen of the best guides to search engine marketing of the past 18 months.

7 deadly sins of Google AdWords by iMedia Connection

Calling AdWords “both an easy-to-get-started and difficult-to-master tool for online advertisers,” Sheri Firstenberg takes a “look at seven AdWords sins that could be killing your ROI,” among them using search network with display select as your campaign type (search and display work differently and campaigns should be managed separately); dropping the ball on ad extensions; and ignoring match types and negative keywords.

New Google AdWords Callout Extensions How-To: Highlight Offers in Your Ads by WordStream

Miranda Miller writes that Google’s recently introduced Callout extensions enabole “you to add more text to your ad to spotlight free shipping, discounts, price matching and more. Callout extensions are similar to sitelinks, but without the links,” then explains why advertisers may want to use them, how to get started, and tips & tricks.

10 ways to get the most from PPC in a small-keyword category by eConsultancy

Using the category of home insurance as an example, Malcolm Slade demonstrates how “how search marketers operating in a highly-competitive category can achieve visibility and acquire new customers without simply increasing their paid search bids,” through tactics like remarketing, ad extensions, and social proof.

9 Pay-Per-Click Tools That Will Help You do Keyword, Ad Copy and Profit Analysis by KISSmetrics

Once you get past the obnoxious pop-up ad here, Gary Victory reviews nine helpful tools for paid search keyword research, including KeywordCompetitor (which shows “your competitors’ paid keywords, ads, and landing pages”) and iSpionage (“allows you to gain insight into competitors’ effective keywords, ad copy, and ad budget”) as well as popular tools like SEMrush and SpyFu.

Your Guide to Targeting Prospects on Google’s Display Network (Part 1) by The Daily Egg

Adam Kreitman explains what the Google Display Network is (“a huge network of websites—from the New York Times site down to tiny sites hardly anyone knows about—that run Google ads”); how it can help search advertisers expand impressions, clicks and conversions; and how to use keyword targeting and management placements. Additional targeting options are explored in part 2 and part 3 of this series.

4 Google Analytics Reports Every PPC Manager Should Use by PPC Hero

Emma Welland identifies four reports within Google Analytics that search engine marketers should be reviewing, and the value provided by each. For example, the Keyword Positions report (found at Acquisition>Adwords>Keyword Positions) reveals which ad positions actually provide the highest conversion rate (it’s not always the top spot).

Help! I Raised My AdWords Bids and Got LESS Traffic! by WordStream

Andy Stefano does the math to show how increasing bids can actually reduce clicks, how quality score can increase clicks without increasing the budget, and strategies to address different search marketing goals (branding, traffic, conversions, or ROI).

AdWords Keyword Diagnosis Report: Diagnosis Statuses Decoded by Search Engine Journal

Reporting that “AdWords provides a keyword diagnosis tool inside the user interface that few people know about, and even those who do use the tool may be surprised to learn the tool is quite robust,” Heather Cooan explains what each keyword status means, from “ads showing now” (what you’d like to see for every keyword phrase) through “low quality score,” “low search volume,” “keyword disapproved,” “excluded” and more than a dozen others.

Crowded SERPs, Top-Heavy Ad Positions, and What It All Means for Your PPC Campaigns by ClickZ

John A. Lee looks into the implications of changes to search engine results pages like product listing ads (PLAs), knowledge graphs, and suggested searches (less space for ad units and higher CPCs), and what search advertisers can do to try to retain top exposure for their ads.

Maximize Your Click Through Rate: Tips on Writing Killer Ad Copy by Vertical Measures

Natalie Barreda explores how to optimize ad copy, from the headline to ad extensions, competitive analysis, and ad body text: “The absolute, most important component when writing ad text to ensure quality clicks is the call to action in the ad. Another important thing to note is the ad relevancy/keyword use within the actual ad copy.”

Going Unicorn Hunting: The Secrets Behind Ads with 3x the Average CTR by WordStream
***** 5 STARS

In this long and detailed post, Larry Kim goes step-by-step through a process to “ads to the point they’re performing in the top 1% of all ads across the platform.” Along the way he spells out the difference between average and exceptional campaigns; the intricacies of AdRank; dynamic keyword insertion; ad extensions; and much more.

The Ultimate List to Clean Up Your PPC Accounts for the New Year by Search Engine Watch

Joseph Kerschbaum details 16 elements that search marketers should review periodically to keep campaigns running in top form, among them geographic tarketing and bid modifiers; ad scheduling; ad rotation and delivery; ad copy; landing pages; and shared negative keyword lists across campaigns (“make sure all of your negative lists are targeted to the proper campaigns. You might be surprised at what you find”).

Rethinking Your Paid-Search Presence by MediaPost

Writing that “Unfortunately, many marketers look at their paid-search keywords in a silo. They get stuck in the channel. They may realize that certain terms work better in paid search, increasing conversions, customers and revenue, but they stop there, rather than integrating these terms across all marketing initiatives — which would provide a far greater impact,” Elizabeth Dillon explains how marketers can and should rethink paid strategies in terms of optimizing overall web presence.

New AdWords Ad Ranking Formula: What Does It Mean? by Search Engine Land

Larry Kim (again) demonstrates how AdRank works in AdWords and how Google uses it to determine “the order in which competing ads should be ranked on a SERP.” He also points out that AdRank “plays a huge role in determining the actual cost-per-click that your competitors [ITALICS] pay when someone clicks on their ads,” and delves into what search marketers should be doing to optimize AdRank given Google’s latest changes to this algorithm.

The Ultimate Guide to Google AdWords Quality Score by PPC Hero
***** 5 STARS

This long, detailed, and outstanding guide is designed to “help you understand the different types of Google Quality Score, why they’re important, the misconceptions about Quality Score, and it will provide you with a checklist of actions you can take to help raise your Quality Score.” This is one worth bookmarking for long-term reference.

Top 5 Ways You’re Leaking Money in AdWords by WordStream

Noting that small businesses typically waste 25% of more of their AdWords budget, Erin Sagin identifies five “culprits” that unnecessarily drain those dollars, and how to deal with each one. For example, not using negative keywords: “If you detect that a searcher is looking for something that you do not offer, eliminate the possibility of showing your ad to them by setting a negative keyword.”

A Guide to Retargeting (Remarketing) for B2B Marketers by KoMarketing B2B Online Marketing Blog

Joseph Vivolo defines what remarketing and retargeting (which are pretty much synonyms) is; dispels common misconceptions (“The biggest misconception is that retargeting is a form of stalking…[but] no matter what, you will find ads on webpages as you browse the web. The only difference with retargeting, is that the next time you see an ad, it will most likely be something that you are interested in”); explains the value of retargeting for B2B marketers; and lists several best practices.

Search Remarketing: What You Need To Know by MediaPost

Contrary to the post above, Jeremy Walker writes that “While each serves to more accurately reach specific audiences, search retargeting and search remarketing are two very different practices.” He goes on to explain the distinctions, benefits, considerations (be prepared for much lower volume), and mistakes to avoid when using search remarketing.

Infographic: Nearly 1/3 of consumers click on paid links by leaderswest Digital Marketing Journal

Jim Dougherty presents an infographic from DMNews containing a number of interesting SEM-related stats, such as that paid search has a higher average conversion rate (2.6%) than organic search (1.9%), and that paid search accounts for 44% of all search engine traffic revenue for online retailers. The figures may or may not be spot on, but the underlying message that marketers shouldn’t ignore paid search is spot on.

Should Every PPC Expert Know CRO? by PPC Hero

Calling conversion rate optimization (CRO) a”a fundamental part of PPC,” Sam Owen lays out the five principles of how good websites work, then explains how to improve your CRO skills using the DHAES approach (for data, hypothesis, approach, experiment, and statistical significance: typically you “need at least 50 conversions per test page”).

Google Rolls Out Metrics Tool, Estimates Conversion Tracking To Improve Bids, Budgets by MediaPost

Laurie Sullivan writes that “The Estimated Total Conversions AdWords tool estimates online sales and conversions that require multiple devices to complete,” and explains how this tool works to “give advertisers a complete view of all conversions driven by Google search advertising…(including) metrics based on phone calls and store visits.”

The 10 DOs & 10 DONTs in Google AdWords by Search Engine Journal
***** 5 STARS

Rocco Baldassarre helpfully provides a reference-worthy list of 10 things advertisers should definitely DO in AdWords (e.g., utlize the keyword planner, hone your ad text, use tightly themed ad groups) and 10 practices to avoid (such as paying “too much attention to keyword popularity metrics,” trying to outbid competitors, and neglecting geographic targeting).

Quality Score Hacks: 3 Sneaky Ways to Increase Your Quality Score by WordStream

After noting that optimizing AdWords quality score can reduce CPC by as much as 50%, Elisa Gabbert explains three ways to gradually improve quality scores, from using site extensions (like sitelinks and call extensions, which are “especially key for mobile ads, allowing people to call you with one click and get what they need right when they want it”) to bidding on brand terms.

Every Adwords Campaign will have its Day by KKSmarts

Writing that “By combining their adcopy with that time their ad is running they will definitely stand out from the other adverts and, as we know, ads that stand out usually get clicked on!,” Mike Seddon proceeds to explain how to use ad scheduling to separate your ads from the pack and increase CTR.

10 best practices for landing page design you need to know by Polaris B

Shelley Pringle shares 10 key considerations for designing an effective landing page, from making the offer clear and “answering, the question: what’s in it for them?” and keeping the form short to using the “blink test” and optimizing your post-submit thank-you page.

10 Alternatives to Google AdWords by PPC Hero

While Google AdWords is by far the largest PPC network, there are times when marketers may need to use other networks in addition to or in place of AdWords. In this post, guest blogger Aleh Barysevich details 10 alternatives, from the obvious Yahoo! Bing Network to AdRoll, “a retargeting platform, which is one of the top third-party tools officially approved by Facebook.”