Can you do a shifty? looks like you are just going for the grab without the shifty.
I find that flat base is better then being on edge. I do one at 3:50 in this video, i should have tweeked it more but oh well. I found that if are at the park witih your board on, just kneel in the snow, then reach and twist and grab your board while throwing your off hand up. This will help you get used to the feeling of twisting and not just grabing.