this is my second time as well, but I'm not nervous, nor was i the first time. it will hurt, i wont lie to you. hurts more after the fact than during in my opionion and i had a second degree tear. i didnt take a single birthing class so i basically relied on my bkdy to know what was happening and everything went fine. youll KNOW when its time to push, you'll know exactly how, because theres not really a right or wrong way. as far as the amount of people, your SO if theyll be there and anyone else you invite in (most hospitals are really good about keeping people out if you dont want them in) your OB/DR and a nurse or two from the hospital staff plus your pediatrician.
i had my SO and both my parents and there were roughly 4 ish other people in there. and even though it seems awkward now, hen it happens the last thing on your mind will be your lady parts all over the room. and i mean the dead last thing.

this is my second time and im nervous as heck girl its okay and its up to you who you want in the room and trust me you will do just great :)