1. Always post ads on content rich pages this will help you immensely, idea is to give adsense chance to work with keywords of your site content and produce high paying ads.
2. Place ads in a way that you don’t have to use words like “Sponsored Links” and “Advertisements” above Adsense code. We know that we cant out Adsenseright below the blog post title and if you want to put Adsense below post title you will have to put “Advertisements” word above ads. SO better is to make some kind of separation between post title and ads.
3. Always place ads above the fold which means that user should not have to move down for ads. This will give maximum ads visibility to user and greater chance to get more clicks.
4. Don’t mix the ads totally in the content make sure there is some free space around the ads.
5. Always do experiments with the placement of Adsense on you site. Because you don’t know what works best for a particular site. You can track the withAdsense channels to know which placement works best.
6. Use both links units and ad units ads. Best place to put link units is in navigation and below the header and put ad units around the content.
7. Always match the color of ads with the font color of you site. Proper lending will make user fail to make difference between ads and site content and will lead to better CTR. You can also change the font family of ads for proper blending.
8. Ad units codes 336×280, 300×250, 160×600, 728×90 works best as compare to other codes.
9. Blend the Adsense ads with the site don’t use any borders of ads.
10. Always do some kind of experiment with the colors of the ads. This will help you to find what works best with your site.
You can add more tips through comments… thanks