Place a piece of duct tape on the top head of your snare drum. Adhere one end of the duct tape to the snare drum head and the other end to the rim of the drum. By connecting the rim to the head, the duct tape will absorb vibrations from the drum, effectively muffling the sound.
Attach a quarter to a piece of duct tape, and wrap the quarter to cover it completely with duct tape. Then place the quarter wrapped in duct tape on top of your snare drum head, taping it to the rim with another piece of duct tape. Do not tape the quarter to the head of the snare drum. This will allow the quarter to bounce when the snare drum is hit hard, effectively dampening the softer snare drum hits and allowing the harder snare hits to ring out.
Tape other objects to the top of the snare drum for muffling. When taping them, place the items off to the side of the snare drum head, so that they are not hit when the snare drum is played. Make sure the items are taped securely to the snare drum, so that they do not move when hit. Items frequently used for this purpose are small pieces of cardboard, cloth and leather wallets.