square your sheet of paper, or use origami paper. A smaller square would be a bit nicer, but it's not necessary.
- Fold one corner to the other
- Orient it so that it's a triangle
- Fold the bottom-left up to the top, repeat with the right
- Release those new left and right folds, so they unfold a bit. You'll be putting them back in place in a second.
- Take the first layer of the top of your triangle, and fold it down to touch the bottom
- Put the earlier left and right folds back up
- Take the top of the left fold, and fold it so its top tip is straight down into the bottom middle edge. Just make a simple crease. Do the same with the right fold.
Those new folds can now be folded the other way, inwards into the pocket