Repeat until the desired pitch is found. One last time, tap around the edge and fix any inconsistencies in the tuning of the head. If you use double headed drums, repeat with the bottom head. Getting the bottom head of a tom to match the top head takes a little extra work. The easiest way to hear the pitch of each head at a time is to muffle one head while tapping softly on the other, then switch.
Snare drums are a bit different.
Basically, the more tension you give the snare-side head, the better snare response you'll get. Tuning snare drums takes a lot of experimentation for each drummer. For the most part, proper tuning techniques can eliminate the need for muffling. Using loose, floppy heads with tons of muffling will leave you with an expensive set of cardboard boxes. Bass guitars love to drown out a fat, dead snare.