From my own experience, I've learned that it is always good to warm up before recording. It's a very basic thing, I know, but you'd be surprised how often people will forget. Another thing I learned from my voice acting, is that it is good to, how do I put this, loosen up the jaw to get ride of as much saliva as possible. What this does is it gets ride of that *smacking* sound that can happen when your singing. Green apples are another great tool to help remove that smacking sound. These are just a few small tricks that I have learned over the years.