I'm doing 2 things
I learned to do this with four friends. We just decided we wanted to learn how. None of us knew how. We all went to a park (stone-cold sober) and just stuck our fingers in our mouths and tried. After much drooling and light-headedness, someone managed, and we gave each other tips until we could all do it.
I do it one-handed, with my thumb and middle finger of my right hand. I put them together like an OK sign, put the join against the tip of my tongue, fold my tongue upward, stick the thumb and finger (still pressing the tongue) into my mouth up to the first knuckle with my lips curved over my teeth, bite down medium-hard (hard enough to feel but not hard enough to hurt), and blow hard.
I can’t make different tones. I have heard, but don’t know, that it is possible for people with tongues that curl to do it with no hands and impossible for people with boring tongues to do with no hands. I have a boring tongue and have never tried to do it with no hands.
