Over time, different people have come up with various ideas on how to maximize profits using AdSense on their website or blog.

I've seen people swear that regardless of your site's color scheme, ads with red backgrounds and yellow text work best, because they stand out.

(For what it's worth, I disagree.)

I've seen people stand by the idea that blended ads work best, because they match your site's color scheme (specificially page background color, link color, and text color) so well that visitors supposedly think it's another part of your site, so they click.

(On this, I tend to agree, but not for that reason, but rather the fact that you're not screaming out that you're begging for money by using some outlandish color scheme. The problem with the blended ads are that regular visitors might become blind to them, and not click at all.)

Somewhere in the middle works best I think. Don't make it look like you're begging for clicks, and don't make it look like you're trying to hide the fact that you're begging for clicks.

Now, for positioning...

Google publishes a heatmap that shows where the best positions are for ads:

It's really quite basic, that ads within content are going to perform better than those in the header or footer of a site. The sole reason for this is that people are actually reading your content, and can quickly become "blind" to ads elsewhere on the site, particularly the text ads that come from Google.

On the heatmap, we see that ads placed at the top of a content block perform best. Second to that are ads that appear above and/or to the left of your primary content. Next would be above the navigation bar, top of the right sidebar, bottom of the left sidebar, and to the right and bottom of the content.

Not performing well at all are top right of the page, bottom right of the page, and below the footer. Let's think about this... oh wait, it's common sense. People read left to right and top to bottom. People come to your site to read your content. Placing ads where people's eyes are going is likely your best shot.

That said - Test your ads. Don't throw them up with the default channel and expect a miracle. Use cusom channel names to test the ads and see what works best for you based on your site's layout and visitor habits.