It can be difficult to get 1 million points in one drift in endurance
races. To get easy points, hold Circle + X. While those buttons are 
held, swing your car left and right on the more straight parts of the 
track to keep the drift going. If you begin to lose too much speed, 
release Circle and press X firmly to get some speed. Keep the car from 
the walls. Once you get your speed back, hold Circle and complete your 
drifting.