Go to www.vandykestaxidermy.com and order a Lutan-F kit. You need to do it right or it'll go to crap. There's a possibility you've already ruined it by soaking it saltwater, but who knows.
Basically, you want to freeze or dry a skin asap after killing (and skinning) something. If you let it stay warm and moist bacteria will start and then when the hide is tanned hair will fall out. If you have a hide you want to tan and don't want to freeze it, then spread it out and coat it in salt. Let it sit for a day, then remove that salt and coat it again with fresh salt. After removing that salt it should be pretty dry. I freeze any furs I plan to tan. Even then you should fold them up and not roll them. Fur is an insulator and hides can go bad in the freezer if you wad them up too tight.
Not knowing any better, I froze a whole red fox. I took the whole thing to a taxidermist for tanning. When I got it back the hair had slipped off the hind leg area. There's a chance that the taxidermist screwed up something, but chances are it took a very long time to freeze and that part of the hide went bad in the freezer.