Pinky Anchoring while slapping

[lonestarwings]

Hi,

I'm learning to slap. I am using Ed Friedland's Slap Bass DVD. When he slaps, he uses his pinky as an anchor. The problem for me is, I have an extremely hard time curling my index and middle fingers for popping while leaving my pinky extended as an anchor. It just feels awkward. Coincidentally I also have a hard time anchoring with the pinky when playing pickstyle, unless I can curl my pinky around the bridge.

On the other hand, when I play, I slap, I hit the pickguard pretty hard with my knuckles, which is starting to become a little painful. Is this pinky anchoring technique a must or can you play in more of a loose fist position with the thumb extended paralell to the string for slapping?

Thanks for the help.