The most basic of all origami hats involves 5 simple folds and makes a kind bicorn like, hat as below
This was made using a sheet of A2 sugar paper, A3 would make a child-sized hat.
The paper needs to be rectangular, not square.
(newspaper works just as easily)
Fold the paper in half (the fold line is across the shorter size)
Position the fold at the top
Then fold the corners in so they meet in the middle as below
Fold the top layer of bottom edge of the paper up, over the folded corners
Then turn the paper over and fold the remaining edge up
That's it your done you now have a hat.