Have enough control that you don't hold yard sales at the bottom of jumps. Don't bleed on tables and boxes. Don't leave dislocated teeth laying next to a rail. If you get hurt, crawl off into the trees to clear the way for others.
Actually, about half of the ski patrol stops I see are in terrain parks. I don't know what the injury stats are for park vs. total mountain, but it seems pretty high for an area that represents 1% of the terrain. Be careful.