My big lesson, particularly if starting new..
NO matter what, there is almost always someone shooting worse than you, so relax and have fun.
My first Highpower match freaked me out, and was convinced I'd come in dead last, shot a 375 - 4x, good enough for the middle of the pack.
The guy having the best time on the range was a fellow about 80 yrs old, shooting the Garand he hid away before leaving Italy after WWII (said he was one of the last out and they weren't hardly checking anything at that point). Out of 50 rds he hit the target 8 times (42 misses). Had a smile on his face the whole time. Told everybody war stories after the match. What a great guy. Learned from that too..you're there to HAVE FUN.
Happiness is a warm barrel!