What braking technique is recommended for a long downgrade to avoid overheating the brakes?

Correct answer to question 137 (Air Brakes): Apply the brakes firmly enough to slow a bit below your target speed, then release, repeating in a controlled cycle

Why

Applying firm pressure to slow below your target speed, then releasing to let the brakes cool slightly before the next application, helps manage heat better than constant light pressure the whole way down.