Ourworkbench-I cut the body 26 inch H X 31 inch W. I cut 4 inches from my corners to make bottom. I hemmed at the top edge, making a double fold of about 1 to 1 1/4 in (I didn't measure). My straps are 78 inches long going from the bottom edge up and back around same front or same back, to bottom again. I spaced them 8 inches apart. I took pictures because sometimes 'people wanna know'. If anyone might be interested I could make a tutorial, but you have the info here, mostly.
copycat-Oly Cloth or Oly Fun as it was called on my roll is the easiest to work with. It's lightweight, not thick so your machine doesn't hang on those bulky seams I sewed flat and best, it doesn't fray or ravel. What more could a sewer want-lol