I have to agree that reading ahead is good and all the things Antares said you'll need to know. For me, I don't really learn anything new until I need it. The sweater looks like it should be reasonably close to easy to do and that anything you need to know that you don't already have experience with you can learn when you come to it. That's my approach. I learned about raglan increases, buttonholes, seaming, and probably a lot more with my first real project, a hooded, button-front cardigan with pockets for my GS. Because he had requested it, I was motivated. I think you're motivated too. I'm confident you can do it.
Listen to Antares and others!
Denial, anger, bargaining, depression, acceptance...the five stages of frogging.