1) Arrive early with ample time beforehand so that you won’t be rushed.
2) Allow enough time to tune, warm-up, play through your piece a couple times.
3) When you walk in to play your solo, just take some time before you play your first notes (check your open strings, get acclimated with the room, move the music stand so that you can see easily without straining). Pretend that you are moving in “slow-motion” and you will actually not seem rushed to the judges. The tendency is to go in the room and start playing immediately without giving a moment to physically and mentally pause before beginning the music.
4) Play as musically as possible (rhythm and good intonation are still obviously very important!).
5) Look at your accompanist before starting to make sure he/she is ready also. You can always ask them for a tuning-note “A” on the piano to do a last minute tuning check.
6) Mentally tell yourself you are going to do a great job and picture yourself nailing every passage! Afterwards feel pleased with your performance and congratulate yourself (we’re often our own worst critic)!
7) Have fun! You obviously love the bass, so I have a great time playing!