beginner trick, just do a butterslide(frontslide) and keep the weight on your heels. sit your ass on the board like you would do if you're just going to crouch down for fun. with your weight still on your heels, push the board forward while keeping it level with the water (toes pointed forward and level as well)
just suck your butt in and lean back and your back should glide against the water. To get back up just lift your head up and dig your heels into the water and then put weight on your back foot. It should gradually bring you back up.
(this is one of the few tricks I can do
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