First thing is ask a boatload of questions about car setup and even radio setup most tracks have a driver that is more then willing to help and even give some poiters on driving technique.
Second you need to go slow before you go fast..... I see a ton of guys who just want to get the fastest car and go as fast as they can and all they do is point and shoot and they get frustrated when they break or cant make the A. dont be afraid to limit how fast your car goes most esc's and radios can be adjusted so you cant go full throttle and dial in some auto brake until you get used to hitting your marks. Dont worry about lap times and results. use some patience it wont happen overnight.
Third is dont give up dont get frustrated after all it's supposed to be fun and realize that rome wasnt built in a day.
last but certainly not least is PRACTICE PRACTICE PRACTICE and more PRACTICE. there is no substitute for track time................