"groin-grabber" dive-between:

setup begins with the frog position behind-the-back cross. then you need to wrap each tail once around the nearest thigh. do this by one at a time unhooking one foot, bending the corresponding knee, looping the nearest tail over that knee (while keeping some tension on the tail so that you don't slip), working the loop down to the thigh so that the foot slips through entirely, then hooking that foot back through the fabric as it had been before. (photos 1-5, above)

now the groin grabbing. there is now a loop of fabric along each inner thigh. grab those loops and pull them forward so they bunch up in front of each hip (photo 6 above). this is where the tails which you are later going to grab will hang from.

now bend both knees to hook the fabric, so you're hanging by your knees instead of the pressure of your feet (7). let your arms go loose and just hang upside down. then beat a few times, swing up, and grab the two poles above your knees (8,9). straighten your legs (10), pass your chest between the fabrics (11), straighten your body and arch your back, hanging in a sort of double "butt-floss" position, ready for the dive (12). variation: straddle instead of holding straight legs together, so that your "butt-floss" position is with straddled legs; this looks interesting, will make the dive faster.

when ready, release both hands at once, and as you fall forward (keeping your body straight), grab both tails in front of your hips and then straighten your arms out to either side (slightly down). (there may be time to pose with arms wide, as you fall, before grabbing the tails.) you end upright, with fabrics crossed behind your back (under your shoulderblades) and slightly tangled.