I wrote this a few months ago for someone else, I copied and pasted then cut out what is not applicable....
You'll likely start in the beginner group, learn the flags get used to wearing a helmet in your car (for me at least was weird at first) and understand the dynamic of driving on the track.
As far as upgrades, I do suggest that you change your fluid to a motul RBF600 or a super blue dot4. its definatly not the end of the world if you dont/cant, but temps get hot out there during the summer and as a beginner nothing is more disconcerting than a spongy pedal. check your rotors visually for anything that may be a crack or abnormality at least halfway through the day. I take a quick peak (with the wheels still on the car) after every other session or so. its a good idea to check oil level and have a peak under the hood for splashing abs fluid and under the back for anything else dripping as often as possible. I bring a peice of scrap carpet/towel with me so i can lay down and not get dirty.
I always put my pressures at 32PSI in the morning and they will heat up to about 36-38 during the track session. after you pull in the first few min try and take your PSI if your in the ball park of 36-38 you'll be good. as it heats up you may need to bleed some air off.
TCS always OFF, sounds scary but is much easier to control if you do step out. I ended up unplugging my ABS on my first track day in the NSX then removing it all together later on. There varying opinions about this, personally I did not like the ABS at all.
take ALL the stuff out of your car. EVERYTHING. floor mats, junk in the glovebox spare tire from the front. certainly don't have anything hanging from the rear view mirror.
You'll notice that during hard driving the gas gauge will start to drop waaay down. For one, your using more gas on throttle (duh) and two theres a quirk in the NSX- After you take it back to the pits it'll typically rise up a few hatches over where it said it was when you were during your session.
wheel to shifter then hands back on the wheel. pet peeve sorry.
One cautionary piece of advise I am qualified to give is is be careful on over revving on a downshift. I es'sploded my oil gear running CCW at streets this last year. it was avoidable but I was in 'the moment' coming down the straight, Ive lived and learned.. and paid for it. If any sort of oil light comes on PULL OFF THE TRACK SAFELY AND TURN OFF THE CAR. Not trying to put fear in you, people track plenty and are just fine. Im just saying- if an oil pressure light or CEL light flicks on. It can end up saving you a wad of cash just to shut her down and get a tow back in. It should be mentioned that the oil pressure gage will be jumping around coming in and out of vtec (thats normal and nothing to worry about) idiot lights mean trouble.
If there is some one behind or in front of you that you dont want to be around, pull into the hot pits (all this will be covered at the drivers meeting) some people forget thats an option.
painters tape. I dont use it. I track a shit tonne and my paint is holding up fine. Im not super anal like that though so, grain of salt. If you do tape the car. PLEASE don't block the radiator ducting hole.... Lemme tell you about this one BMW driver...
You can also run as little/much as you feel comfortable with.
Heat out there is a bitch i typically will sit out a few during the day to hydrate. there is free water bottles typically, drink it.