There are many people who have their Adsense account disabled and they are completely lost on what to do next. I have been on Adsense program for a year; encountered people complain about how their Adsense account being disabled. 
Frankly speaking, many of people have their account disabled or banned due to fraud. Google are extremely strict when it comes to fraud. For an example, many publishers click on their own advertisements to ‘steal’ money from the advertisers. In order to protect the advertisers, Google has to take drastic action to disable or banned you from the program; and return the money back to the affected advertisers.   
Anyways in this article, I would like to share with you some of the common mistakes and tips to prevent or minimize the risk of Google to disable or banned your Adsense account. 
a) Do not click advertisements on your own website. Google has a very powerful tracking tool to detect frauds, especially if you click on your own advertisements. Many newbie doesn’t aware of this until their account is being disabled due to this reason.
b) Always play safe. Report any abnormal activities to Adsense immediately. Example if you notice any of the below activities
– If you accidently click on your own advertisements
– If you notice suspicious clicks, that coming from a certain country or website
– If you notice a significant increase of traffic to your website
– Anything that not normal or suspicious 
c) Always read the Google Adsense Terms and Conditions (TOS). Most of the Adsense publishers never read the Adsense terms and conditions, so often people have their Adsense disabled due to non compliance. Also do not ignore warnings or questions from Google, always response to them at soonest either thru email or website.

d) Having multiple Google Adsense accounts. In the Google Adsense TOS, each person can only have one Adsense account. Surrender to Google, if you are having more than one Google Adsense accounts before they catch you. Google has a very power tool to detect multiple accounts that belonging to same person.