I used to do this, and if I remember correctly, it's really bad for your wrists. Do a couple standing BHS's with chalk on your hands so you can really visualize where they land. You can also go back to doing them over a BHS trainer a few times "slow-mo" just so you can get your hands lined up right. I found that my hands used to point out more when my arms weren't straight, so you could also focus on general form in the BHS. (Pushing out with your legs and not up) Other than that it's merely repetition with hands facing the right way. Good luck!