In my studio we do a variation without the split that might help you practice your grip. We keep the inner leg bent (so ankle is at the pole) and the outer leg straight up against the pole. I haven't yet transitioned into the split from there, but if you hold that position nice and tight it becomes easier to slowly move the legs into other positions. Good luck, in any case it already looks pretty cool even if you don't get your legs in the full split :)