Dan Grading

Hi guys, I just wanted to get the opinion of some other martial artists on things you can do to prepare for a Dan grading, and particular things you can do to perfect Forms etc or just to mentally prepare. It would also be great if I could get some feed back on how to deal with the stamina behind an 8 hour Dan grading. Any help that any body from any style can give would be great, after all where else should could I get honest guidance (Sensei Excludued of course as they are already helping me deal with this) I just feel that it would be beneficial to get some other views from other experienced martial artists.

Thanks

Mike Sheffield