you'll find that all your advisers / frocos / even upperclassmen will be very helpful when it comes to picking classes
there will be opportunities for bluebooking parties (where people get together and sit around sifting through courses, getting advice from people who have already had said courses and professors, and throwing around class ideas)
there will also be plenty of explanation of how to do everything
they make it very simple, and it's one of the best course selection processes there can be, because usually you aren't excluded from a course because of time-sensitive registration and usually if you're prepared for the class, you can talk to the professor and they may let you in
(sometimes they won't, especially if it's a junior/senior seminar, but it's ALWAYS worth a shot)
so hold your worries on registration until you get to yale and just focus now on picking out interesting classes and be prepared to make sure you pay attention to the dates of preregistration and academic fair and placement tests of the first week or so at school