Quote Originally Posted by pooks
I'm trying to figure this out ... ? He does what with the markers? (Are you talking felt tip markers?)

If you go to a bike shop and sit on one of their measuring devices, is that the most accurate? I have this image of me putting my well-padded bum down on it and leaving behind nothing but a smooth surface with a ridge where my crack is, sigh.

ETA: When I tried the "sit on a curb" method, I ended up with a piece of paper that was dimpled/pimpled with little indentations where the rough concrete had almost pierced it, in two roundish circles, but no clear definition where the bones were.
measure from center to center of the indents, but imagine if you will, a bike
saddle. you'd want it to support a little of the area around it too.