Known as an e-brake across the pond. The handbrake is a popular way of inducing a drift and is often used in conjunction with other techniques. You should ensure the ratchet mechanism on the handbrake is disabled so it can not lock into position. You should have uprated pads/shoes and preferably upgrade to a hydraulic system. As the pads may not have chance to reach temperature, make sure the brake compound is good across the full temperature range.
1. Enter the corner at a speed which will normally induce understeer : front wheel slip
2. Drop down a gear (preferably using heal and toe) so that you are in your power band.
3. Turn into the corner hard!
4. At the apex of the corner, dip the clutch, then pull hard on the handbrake for about half a second to one second.
5. The instant traction is lost, pop the clutch back up and come on the power hard.
6. The rear end will step out and you will be in drift. Finish the maneuver as before.