Any question answered...

No sewing required as long as you use something like a piece of waxed cotton or similar. Roll it up like a taco and ay wala.

Bit late but just to add, once you know the height of the taco shape you want you can then iron creases where you want the folds.

This will make it look neater and a bit quicker to fold.

If it's wax cotton remember to put a tea towel on the top and bottom.