Hi Jerry. Yes, you can use either. I like 50% rubbing alcohol. Even if you form it tight, it will break in with use, but if you have concerns of it being tighter than you might want, wrap the blade and grip with duct tape. Build it up a little, not too much though, then wax coat over that. That will also help protect the blade while it dries, and make it easier to get back out. Let it dry thoroughly before you remove the knife. After thoroughly dry, oil the leather. Neats foot, or plain ol mineral oil.