Following your surgeon's Post Operative Care Instructions is primary and vital.
The odd horror story we sometimes read about are always the result of lackadaisical attitude of not really following the Dr.s advice on what to do.
Sleeping on your grafts, washing too vigoursly the 1st week, not washing at all, picking at the scabs too soon or letting then stay stuck to your scalp too long, all bad stuff.
It's not so much what you can do to insure survival, but what you need to avoid so you don't mess up the transplant.