No doubt there more than 25 ways to display Google ads on your website like you can display ads in ad units, link units,
adsense for search, feeds and mobile contents but with respect to those who still are finding the best paying google ads
slots then they should prefer adsense for contents (ad units). And more specifically the ads slots of leaderboards in header
and footer of your webpage square (336x280).
If this ad slot is placed just below the content,article or post of your blog more likely visitors are going to have click on that.