A drivers license suspension or revocation can happen for a number of different reasons. Some examples include a DUI, reckless driving charges, too many points on your license or unpaid traffic tickets.
The best time to take action to prevent the revocation of your license is to deal with the underlying charges that can lead to revocation, at the time they happen. For example:
If you are found guilty of a DUI charge and you believe that there was something wrong with the verdict or the process by which it was obtained, you can appeal to the court for reconsideration on that point. The case can be reviewed by an appellate court before the conviction is one that becomes final.
If you cannot defend yourself against the charges, the court may revoke your license. At this point, you can attempt to file an appeal with the court in order to argue the revocation was improper or not warranted. This may not get you very far, though, since there may be mandatory minimum license suspensions for various offenses.
There are also times when the DMV may revoke your license through administrative action. For example, in some states this occurs automatically if you are charged with a DUI. You can appeal this revocation by requesting a hearing with the DMV. You'll need a reason to appeal it (i.e., a reason why the revocation was improper.) If the DUI charges against you were dropped, that is a reason to appeal your DMV administrative license suspension.
If you do hope to appeal charges brought against you or if you wish to get your driver's license revocation reversed, you should strongly consider speaking with an experienced lawyer for assistance on how best to proceed.