Take it easy - don't buy more than you have to before you understand your instructor's preference. I'm up to the nav section of ppl training and to a large extent, your job as a student is to listen carefully and do what you are told. There are many ways to instruct and to fly so you have to be guided by your instructor.
If you want to get a head start, download CAP 413 from CAA (Radiotelephony) and read the text on the subject. Understanding what is being said (and why!) will reduce your workload and speed your progress in the air.
Good luck. Fun time ahead eh?