The longer you put it off the more you will forget. Ask me how I know this. You have to bite the bullet, get something - calico perhaps- up on the frame, and just do it - experiment - try different designs free-hand to get the feel of it. don't race along, just take it steady, it will come back to you. Most of all - enjoy the experience and don't panic if things don't go right the first time.
Cheers