After using my pocket tarp a lot, I decided that I should have gotten the one with doors. The doors add privacy and trapped warmth, they make the space feel bigger, they make a nice vestibule for my pack and shoes, they protect from unexpected rain (the pocket tarp sleeping space is unreasonably narrow at only 26″ wide), and my make-shift doors fluttered too much in strong wind. So rather than buy another pocket tarp I decided I could probably make doors.
I think it came out well for someone with only marginal skills and no experience working with DCF.

The doors are separate. Originally I had imagined making just an extended one-piece beak, but I decided I two separate doors might be easier to make.

The doors overlap and I used little plastic rings to make it easier to clip into the mitten hook. I put the door closing thingies on last so that I could make sure the doors closed tight. The overlap was more than I expected, but I’m no architect or engineer or geometry major.

Even with the doors it still fits in the small bag it came in.
Lessons learned:
Do not even attempt to sew through DCF tape. It will ruin your needle. Even your hand needle.
DCF is really hard to cut, especially in one direction. Smooth scissors work better than serrated ones, especially in the easy direction. A utility knife works well in the easy direction but not in the hard direction, at least mine struggled to cut cleanly in one direction.
Peeling the tape off the backing is really frustrating. After a while I got the hang of taping long sections of tape. I saved the taping of the seam where the doors attach for last once I got used to the tape. The doors are sewn on and then taped for extra security and water resistance.
I used masking tape instead of pins but had to move the masking tape as I went because the sewing machine would make a better alignment of the material than I did taping it.
Other than that, it’s easy to work with. You can fold it over and it will stay folded for you to tape or sew.

