When in doubt, HOLD YOUR LINE.
I've seen so many beginners see a faster rider approaching and try to do the right thing by getting out of their way. That is the wrong thing to do. Just hold your line and the faster rider is already planning on how to overtake you. The worst thing you can do is change your path.
Also, when you finish a race, HOLD YOUR LINE and your SPEED. Don't swerve up-track to scrub off speed. You must remember that there are riders barreling in behind you with a full head of steam. If you change your line or speed, they might run into you. Simply carry your speed around turns 1/2 and then look back when you exit 2 to see what's going on and if it's clear to decelerate.