Top 10 mistakes, you should never do with Adsense.
1. Do not use fake information when opening your Google AdSense account.
2. Don’t advertise anything on Google’s prohibited items list. It’s a lot shorter lists than PayPal’s or eBay’s.
3. Don't "beg for clicks" or provide any incentive for clicking on your Google AdSense ads.
4. Do not display AdSense ads and a competitor's ads (like Overture's) on the same page at the same time.
5. Keep AdSense ads off of your registration, confirmation, and all "thank you" pages.
6. Never click on the ads running on your own site, even if you are genuinely interested in the product or service and are thinking of buying it!
7. No misleading labeling Google is very specific about what text can be placed around their ads. No text other than ‘sponsored links’ or ‘advertisements’ is allowed.
8. Avoid keyword spamming and other divisive tricks You may be tempted to buy.
9. Do not modify Google AdSense code other than to change the parameters that Google authorizes you to change.
10. Be honest with Google ! Yes, be honest about all the nine pionts above and make real money with Google Adsense.