1. Start with an open square
3. Then fold again in half (be careful to have unpretty edges facing up rather than the table)
4. Take one side and fold it to leave about an inch gap at the other end...
5. ...like this
6. Then take the opposite edge as above...
7. ...and fold that over just it's own length
8. pick up and slot into breast pocket
9. Adjust to your personal liking. And you have done a straight fold.