Practice, Practice, Practice.
Practice on the ground with a compass. Measure your paces. Practice distances with walking.
Create a course for yourself and friends (at least a buddy) underwater. Measure a distance and calculate your number of kicks from point to point.
Get accustomed to noticing your compass during your dives. Take note of how current affects your movement from point to point.
Get comfortable using your compass when you don't really need it, so when you do need it in cloudy water or night diving, you'll be comfortable.