The Parish Register of General Vestrypersons will be open for revision only during the month of February.  If you're already on the list you don't need to do anything, but if you're not and you do want to be registered as a General Vestryperson and take an active part in the running of the Parish, then you should speak with the Rector or any of the Churchwardens who will be happy to tell you what steps need to be taken.  It's really quite simple and when formalities are completed it gives you the right to vote at the General Easter Vestry when members are elected to the Select Vestry and other church positions.