Practice the following exercise on a metal chair. Sit in front of a metal chair set on a hardwood or tile floor. Identify the parts of the chair as they relate to a drum set: the right chair leg is a cymbal, the left leg is the snare. A tap on the ground with your right foot is the bass drum and a tap on the ground with your left foot is the hi-hats.
Play quarter notes with your right foot. Quarter notes break a full note up into four equal parts. Keep this rhythm for eight counts to get used to it.
Add in eighth notes with your left foot. Eighth notes break a full note into eight equal parts. Play with your right and left feet simultaneously for eight counts, or until you get used to it. This is called two-way coordination.
Incorporate your left stick to play eighth-note triplets against the left leg of the chair. This is called three-way coordination. If you get tripped up here, return to Step 3, take your time, and begin again on Step 4 when ready.
Attempt sixteenth notes on the right leg of the chair with the right drumstick as you continue with the first three parts. Continually pay attention to both feet and drum sticks to make sure they aren't syncing up to the same rhythm. This exercise takes time to master. Always repeat the previous steps if continuing is too hard at the moment.