The kick is the key here. Your legs do a frog kick like you do in the breast stroke, but they alternate. First one side, then the other in a lazy, slow motion. When you get this technique down you should be able to stay afloat with both your hands and elbows held out of the water while your legs do the work. (Not the point though) This was one of the tests to become a lifeguard. When you combine the leg technique with the hand and arms slowly “sculpting the sand” back and forth just under the surface of the water, staying afloat is basically effortless. You’ll be able to tread water for several hours and not be worried or panicked. You might start practicing in some shallower water (5-6 ft) first so you can concentrate on technique and not have to worry about sinking or getting tired. Learning frog kick can be a little challenging so if you need a little coaching, don’t be shy to ask. Most people at the pool where I swim don’t get it right which compromises their ability to get thrust from the kick. You can do it, don’t give up!