As Terry says, many people are happier as snap shooters.
However, if you want to hold, there seem to be a few key factors you have to learn to deal with. Everything has to be solid enough so you don't start shaking as you hold. The meaty part of your bow hand between your thumb and your lifeline should be solidly pressing forward against the bow grip when you draw the bow. Your fingers should be lightly curled around the handle so you don't have to reflexively grab the handle to keep it from jumping out of your hand when you shoot the bow.
Your string fingers should be hooked around the string enough that you don't feel like you're having to strain to keep from shooting the bow until you're ready. I'm not convinced that a deeper hook than that adds anything to the shot, but you need at least that much of a hook.
There is a sweet spot you can reach as you tense your back muscles where it feels like you are holding the bow with them and have minimal tension in your arms and shoulders. Everyone has to discover how to do that for himself. It is difficult to explain or demonstrate.
Not just me, but everyone I have read or listened to has to fight the same urgency to get rid of the arrow too soon, including Rod Jenkins, so I'm sure he will discuss that with you. Even snapshooters. The best thing I ever did for myself was to learn to anticipate this urgency rather than dread it, and just view it as a normal part of the shot. There are many other ways to deal with it, including those discussed by Joel Turner in this forum. Don't think it will ever go away; it may well get worse as you get to be a better shot. You just have to learn to deal with it.
At the point of release, you will begin to relax various muscles which are better held in tension until after the shot is released. The extent to which you can hold this tension until the shot is released will determine how good of a shot you are. You will have your share of good, explosive releases, and your share of crappy releases. Learn to become aware of the difference, other than just by the result.