//www.youtube.com/watch?v=YApWFhT5xik
Check out this video of Jeff Glover sharing some concepts on how to set up the hanging triangle. He uses the same ideas shown in this video to set up triangles from the back, half guard, side control, and from standing. Come check out this series if you like to use triangles as it's an eye-opener on how you can set up triangles from pretty much any position!
FANTASTIC drill. Glover as always bringing something awesome to the table. 
Who has two thumbs and loves he hanging triangle? This guy! 
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I do a similar technique to this one with a few differences. Brilliant stuff from one of my favorite grapplers ever