You Can Learn a Lot by Watching
In between your runs, you also need to use your time effectively. After your first run, you may have some idea of which corners are toughest, or where you seemed to be slowing down too much. Watch the other competitors to see what line they’re taking through that portion, and watch where everyone seems to be having the greatest difficulty. As you watch, try to visualize in your mind what the course looks like from the driver’s windshield so you’ll have an idea of where to go when you’re on the course.
Many autocross events will require competitors to act as corner marshals on the course, with their primary task to replace cones that are knocked over and to help the starter make sure the corner is clear. These are excellent opportunities to get up-close-and personal as other drivers run the course. Check out the techniques of the fast drivers and see how they are taking specific corners. Their experience may help you take seconds off your own time.