While you are not required to have a criminal defense lawyer handle this Motion, there are many things a lawyer can do to give you a better chance of success. For example, an experienced criminal defense lawyer can attempt to convince the prosecutor to agree with the Motion whereas you should not speak with the prosecutor under any circumstances. It may also be worth speaking with a criminal defense lawyer to see if the Judge on your case has particular guidelines such as a certain term with the ELMO that must be completed before he or she considers your Motion. In my experience, you will have your best chance with the right lawyer. Good luck.
I agree with the previous answer. Moreover, you will need to understand the exact status of your case (sentenced to jail vs probation with back-up vs probation with no sentence -SIS) and whether you are technically in the custody of DOC or P&P. Procedurally, the two are different.