Fish sometimes bump or nudge a crankbait before really taking it, and even when they do hit it hard, you should resist the temptation for a hard, fast hookset.
Think horizontal. When you want to set your hook, sweep away from the fish with a sideways motion.
One mistake that many anglers make is to have their drag set way too high. Turn your drag down a bit, softening the hookset slightly. That will help prevent you from ripping your crankbait free, or worse yet, bending or breaking a hook.