Oh my goodness. The more you watch musical offerings the more styles of waving your arms you will find. I found a VERY accurate and funny presentation of conducting styles. You MUST click on this link!!! I know I have seen most of these in my lifetime but thankfully have never been on the receiving end.
Check out these styles:
1. The Pinwheel
2. The Basketball
3. The Bruce Lee
4. the Disembodied Hand
5. The Surprise Attach
6. The Big Wheel Keeps on Turning
7. The Big Wheel with Pinwheel Combo
8. the Catch and Release
9. The Stir the Soup
10. Cut Off with Warrior Pose
I recommend that if you are a caught in any of these styles, go take a course or watch really good choirs and see what type of conducting has made it happen.
Be clear, be precise and above all else, make certain you and your choir are on the same page with the understanding of what your gestures mean.