Don't miss Part 1 of this series on swim-stroke efficiency drills.
The following drills not only help develop your kick, but improve your rotation and body position as well.
These drills are easily incorporated into your warm-up and cooldown and should yield good results if done consistently. Remember, if good technique were easy to come by, everyone would have it.
Discipline yourself this season to make these drills a part of your regular swim regimen.
Kick on side: Kick on your side with both arms at your side. Play with head position and see how that affects how your hips ride in the water. (Think "downhill" head pushing down and out and help your hips ride high).
Kick on side with rotation: Same as above, except after a six-beat kick, roll to your other side, initiating the rotation with your hips and core (the shoulders and upper body will follow).
Kick on side, arm out: Lie on your side and kick a length of the pool with the bottom arm extended and the top arm at your side. Concentrate on feeling long.
Kick on side, arm out with rotation: Same as above, except after a six-beat kick take a complete stroke (one-stroke cycle) and roll over to your other side. Lead the rotation with your hips, not your shoulders.