CS
One of the most effective shots in badminton is a well-disguised drop shot. Here are my top tips for making it harder to read: 1. Use the same preparation as your clear - identical backswing 2. Contact the shuttle at the same height as you would for a clear 3. At the last moment, decelerate your racket and slice underneath 4. Follow through gently rather than stopping dead 5. Watch your opponents feet not the shuttle after you play it Practice this by alternating clears and drops in feeding drills. Your partner should not be able to tell which one is coming until the shuttle leaves your racket.
PP
This is exactly what I have been struggling with. My drops are always obvious because I slow my arm down too early. Will try the identical backswing tip at training tonight.
TH
The slice drop is devastating when done well. Another tip: vary the pace. Sometimes play a fast attacking drop, sometimes a slow spinning one. Keeps your opponent guessing.