Eight hours???!!!!! Good luck. Start slow and test your limits. If she is experienced she will understand this. Make sure you tell her just what you want and experiment to see what you like the best. When I first started I never thought about being kicked from behind and I discovered it was one of my favorite ways to be kicked. Don't get kicked hard at first, build to it and you may even find you don't need to be busted really hard to enjoy it. I know for me I found that getting slapped by the foot between my legs allows me to take more of it and it lasts much longer, the pain building in my crotch and it is a real turn on for me. Most important, relax and have fun. Be open and honest with her and you should have a good time. Good luck.