: Fold the left and right corners into the center crease so they meet in the middle.
Could you clarify if you meant (the mathematician), a specific RAR archive file , or something else entirely? Fgronov rar
However, if you are asking how to (a common topic for "making a paper covering"), you can follow these simple origami steps to create one without needing glue or tape. How to Fold a Simple Paper Envelope : Fold the left and right corners into
: If you need a more professional look, use glue and scissors to follow step-by-step official envelope tutorials . How to Fold a Simple Paper Envelope :
You can make a standard envelope using a square piece of paper by following these steps from wikiHow :
: Position the paper like a diamond and fold it in half, corner to corner, then unfold it to leave a crease.
: You can use old book pages to make "teeny tiny" envelopes by following guides from creative crafters .