Drifting corners is no problem on pavement. First, get used to skidding in a straight line; get going at a resonably good speed, then lean your weight all the way forward and jam on the rear brake. After a while, you'll get to know where you and your bike balance re. deweighting the rear wheel. When you get good at this, try to skid in a straight line and tweak the rear around with your legs. Get good at that and drifting corners should be no problem.

I learned this way on a track bike, then I applied it to a road bike and still use it.