flashcards, lots of drilling, repetition. If you can put everything on flashcards and drill them every day that helps. Also with orgo the key is to do active learning and constant drilling. if you can do old practice tests and make a list of problems covered in class on a piece of paper and drill yourself on them (write them out) frequently that'd really help. that really helped me. NMR - you can find lots of different packets online for it. the key with nmr is to know that the shifts can very quite a bit from the numbers you memorized and to draw out all the pieces and numbers of hydrogens attached to neighboring groups. Also do any synthesis practice your instructor provides you (my class had huge packets). In honesty I overstudied for everything except NMR because it's a wild-card, even if you know all the details you can still get the wrong answer really easily, and usually if you write down the fragments you get a lot of the points anyway. I've had nmrs where I got the exact right answer but it wasn't right because of some cheap technicality that wasn't taught.