Just screw it all the way in. That should emulate a blocked off leak jet. Then, you can unscrew it, a 1/4 turn at a time, until it starts to rev how it's supposed to. You're just going to have to tune it. There's no magic to it, and no perfect setting for every engine. Just gotta try and tune it in. Tuning an FCR is a process, but if it's done properly, you'll have a lot more fun every time you ride, and the confidence of knowing that you did it yourself. Have you read through the jetting guide on the forum? If not, I highly advise that you do. Good luck.