I once saw a guy listen to the theme song of Tog Gun while on grid.. a joke, obviously, but it just added insult to injury that he DNF'ed the next run.
If being relaxed induces better driving, try out some relaxing music..
While more of an 'instructional read' than a mantra for driving well, some have printed out Andy Hollis's 'Driving Tips' and poured over them before driving.. maybe it fills the brain with the right words..
http://www3.telus.net/solomotorsport/andy.htm
What do I do!? Stay up late the night before, and if the situation permits, socially imbibe spirits. The success of this, however, has only been based on the results turned from mazda’s ‘revitup’, where I’m sitting in the 95th percentile, with having (barely, mind you.. rear wheel in front wheel drive) taken down a cone on the fastest (first) run. That night’s/morning’s event was a bachelor party.