In Nebraska, if you are convicted of a state or federal felony, you temporarily lose your citizenship rights including your right to vote. Your voting rights are restored two full years after completing all of the terms of your sentence whether it includes incarceration without parole, incarceration with parole, probation or any combination of sentences. (There is an exception in cases of treason).
There is a link below which you can use right now to register to vote.
This page provides information about your voting rights and how to exercise them. The page also provides information about how to find and contact your elected representatives.