Four Simple Steps To Effective Radio Use:
1) Who You’re Calling (Vaziani Tower, Nellis Ground, etc.)
2) Who You Are (Falcon 1 .. 1 F-16C, Hawg 3, two A-10s, etc.)
3) Where You Are (Hardstand Parking, 10 miles south, SE EOR, etc.)
4) What You Want To Do / What You're Doing (Taxiing to Runway 3L, Inbound to land, Downwind Runway 13, etc.)
“Mic Fright” can be overcome by saying what you want to say to yourself and then key the mic and say what you just said.
Nobody expects you to be perfect, but if you check off some version of the necessary info as laid out above, you’ll be way ahead of the bulk of online flyers.