Learn "blast beats," which are the foundation of nearly all thrash metal drumming styles. Use your dominant hand to hit the ride cymbal as your feet hit the bass drum. Alternate between both motions until you can confident of playing them fluidly.
Using your right leg, hit the bass and high hat. Between those motions, hit the snare drum, essentially, you are playing sixteenth-note strokes with your hands, and eighth notes with your feet. The power comes from the combination of the bass drum and high hat, with the latter device giving the illusion of greater speed.
For an extra dimension, add the "gravity blast" beat to your bag of tricks. Rest your drumstick's shaft on the rim of your snare drum. Move your hand up and down, with the stick's head striking the drumhead. The drumstick's shaft should hit the rim on the way down. This is based on an old jazz technique perfected by drummers like Buddy Rich, allowing the hand to pull off two strokes instead of one.
Work slowly up to your ultimate blast beat speed, which can range from 180 to 300 beats per minute. If necessary, count musical passages aloud, breaking them down into "ones" and "twos." The most common expression of this approach finds its way into a 2/4 time signature, which is really a speeded-up version of rock's prevailing 4/4 beat.
Use your bass drum pedal. To produce the relentless driving beat that serves as the genre's defining stylistic signature, work bass drum pedals with both feet. This will also enable you to cut through a muddy sound mix in a live situation. If precision is your goal, play with one foot.
Sharpen your bass drum precision with the so-called "heel to toe" technique. Suspend your foot above the footboard of your pedal. Play the first note with your heel, snapping your foot upward. Bring the heel off the footboard, bringing the toes down for a second stroke. Faster bass drum rolls is the reward of getting this technique down.