your site has to have some content and has to attract the visitor. that way they not only read your site but also come back. and as advised above, blend in the code with your site layout. that way your visitors will click as they read. your main focus should be how to provide a service to your visitor, not how to get more clicks. once you provide some service to your visitors, the clicks will follow by itself
Bring more traffic to your site by doing the seo perfectly. Create good contents and optimize them with high paying keywords. Blend the ad with the contents in such a way that they do not show off. For placing the ads at correct position you log into your adsense account and study the adsense code placement topic. That will throw more light on it. Best wishes for a higher earning
I agree with others that blending is the key here. However, relevancy is also important. Are your ads relevant to your content?
Just try some different ad placements. And pick out the right colors to make your ads blend well with the rest of your site.