Most of us had a forum to exchange ideas. But most had not fully promote Adsense ads. Google had suggested a few ways to increase the clickthrough rate effectively.
When Amit Kumar co-founded MegaGames Forum in 1998, Google Inc. was being run from a Menlo Park garage and AdSense didn't even exist yet. Fast-forward 9 years to 2007: Amit still runs MegaGames Forum just as a hobby, but he earns enough revenue through the AdSense program to run a dedicated server and continue growing his site.
Amit wasn't so successful with AdSense right from the start. When he first started using the program in 2005, his earnings were nothing to write home about, and it was largely because he chose his ad placement, formats, and colors at random. After recently optimizing his ads, however, Amit was able to more than double his AdSense revenue and even improve the user experience on his site. Results may vary since every site is unique, but here are some tips that any forum site, large or small, can also try out to increase revenue.
The welcome box ad
Many forums have a message above the fold on their pages welcoming users to the site and encouraging them to register. Placing a large (336x280) or medium (300x250) rectangle next to this message catches users' attention right when they walk through the door (so to speak). By the way, these are our best performing ad units, and may also increase the number of site-targeted ads on your pages.
The forum post ad
Based on previous testing, integrating ad units into your page content can improve clickthrough rate (CTR). It also provides a better online experience, since your users see relevant ads side by side with normal content. In forums, the highest visibility content is often the first post, so it makes sense to place the ads here. Again, large and medium rectangles are your best bet!
Blending colors and breaking down borders
Colors are important for making an ad visible to the user, but they should still blend with the design of the site. Removing the borders on your ads helps even more with this concept of blending. Don't worry -- even with a well-blended implementation, the 'Ads by Google' label keeps your users from confusing ads with content.
Bonus tip: Improve ad relevance with section targeting
With forums, the first post often contains the most relevant content on the page. By using the section targeting feature to emphasize this content, you can potentially increase CTR with better targeted ads. Visit this 'section targeting' link we mention for instructions.