This model has two versions with a couple of slightly different folding methods for the first one. They look very similar and they are all simple to fold.
The main difference is in the the length and angle of the offset flaps, and the secondary difference is the pattern of crease marks on the front and back of the folded letter.
VERSION ONE (Wide offset flaps).
This version has flaps that come more than half way across their quarter square. The front of the letter has additional creases on the diagonals but none on the back.
This alternative crease pattern has a slightly different way of deriving the creases for the tuck-under flaps. The result looks the same from the front but there is an X crease pattern on the back. It is only minimally easier to fold.
Take your pick. Use whatever floats your boat.
VERSION TWO (Narrower offset flaps)
This is the easiest version to fold. The flap is exactly half of the width of its square and the slope is therefore steeper than Version 1. The detraction is that it has a busier pattern of creased squares on the front.
