State and federal laws impose stringent requirements on individuals who are granted a commercial driver's license (CDL), because of the dangers associated with driving passengers or driving large vehicles on the open road. As such, drivers with a commercial license are expected to practice rigid adherence to the rules of the road and failure to do so can result in suspension or permanent loss of a CDL.
If your CDL is revoked for life, there is very little you can do at that point. In most cases, the rules that lead to the revocation of your license are mandatory; there is no discretion. You are also not permitted to get a CDL in another state if your license was revoked in one state (and the Interstate Driver's License Compact through which states share information about driver licenses ensures that isn't an option).
Your options once your CDL has been revoked for life, then, are to argue the revocation was improper in the first place. Doing this is going to be almost impossible. Once a guilty verdict has been entered against you and you have either chosen not to appeal it with the original court or exhausted all of your appeals, that guilty verdict is on your record. You can't argue that the verdict shouldn't lead to revocation if the law says that it does. Your only real option would be to argue that the convictions that led to your revocation never happened at all (if it really didn't) or that there was a case of mistaken identity (if there was.)
The best way to avoid loss of a CDL is to avoid the convictions in the first place by challenging the charges at that time. For example, you can either argue something was amiss in the circumstances that led to your citation or arrest (i.e., if you were arrested for a DUi, you can argue that the breathalyzer machine wasn't properly calibrated) or that your rights were violated during the process of obtaining the evidence used against you (i.e., that the police engaged in illegal search and seizure.) If you can challenge the charges in the first place, you can avoid the conviction that leads to the CDL suspension.
To get help dealing with citations or charges against you, you should always contact a lawyer. Your CDL allows you to make a living and a lawyer can help you to explore all potential options you have to avoid losing it.