Ok, I chose my fabric: a blue-green flowy gauze, and I have made my pattern. It's not necessary to make a pattern, and the tutorial doesn't call for it, but I like to measure and draw only once. Should I want another pair of wrap pants, (and I do, indeed, want another pair of these) then I will not have to do any of that work over again.
HINTS, so far:
About the crotch measurement:
The big U-shape in the drawing on the tutorial is your crotch seam. To decide how deep to make that, measure from your belly button to your back waist (where you like your pants to sit). Divide this measurement by two, and voila! That's how deep to cut that.
On the tutorial she mentions to make it as big as your head?? I assume she meant the width of the opening, since you can easily measure for the depth. So, I made the opening as wide as my head., 7 inches.
About your fabric.
The stretch of the fabric is important. If you don't place your pattern on the fabric the right way, the pants can be binding and uncomfortable. You want the stretch of your fabric to stretch AROUND your butt, so be mindful of that when deciding how to place or draw your pattern.
About your waist measurement:
Do not measure at the smallest part of your waist. Measure at the place you usually wear your pants. This was a big deal for me, because I where I wear my pants is 4 inches bigger around than the smallest part of my waist. My measurement was taken about an inch over my hip bones.
Good luck!! It's 8:30 now, and I'll add the next step on Friday. Make sure you ask your questions in the comments box!!