I'm glad I never had all this before my first ever track day or I'd probably never would have had a go.
The relevant post for first-timers is Kevin's of 27th Feb @ 10:42.
Ignore the rest and have a go.
That's not to denegrate all the other advice, I too have roll protection, fire extinguisher & firewall - but you don't have to have it, that's the point of a track day.
Jerry.