First, you wanna make sure your snare has a steel shell. If not, then don't do this unless you don't wanna get the timbale sound. I would prefer you use a snare drum that does not have any of those ridges, or humps on the shell. The snare drum I used is a regular Pearl steel shell snare. It has no ridges. Oh and make sure you have a screwdriver handy.
Step 1: How to Make a Timbale Out of a Snare Drum: Step 1
Ok, first your gonna have to take the snares out. Turn 'em off and un-tighten them. I can't tell you how to do the rest because your snare might be different than mine. Note: All pictures taken were of drum after completion, but still shows you steps.