The helmet base is a simple origami base form that gets its name from the fact that it is closely associated with the traditional origami samurai helmet.

To make a helmet base, start with the patterned or colored side of your paper face down. Fold the paper in half diagonally to make a large triangle. Fold the left and right corners to the tip of the triangle so you have a diamond shape.

To make a small helmet for a toy to wear, use regular square origami paper. To make a hat for a child to wear, use newspaper.

Follow these steps to fold your helmet:

1. Create a helmet base.
2. Fold the bottom flaps on your helmet base straight up to the top of the diamond shape. Fold the flaps out at an angle to create the decorations on the helmet. The exact angle of the fold doesn't matter, as long as the folds are symmetrical.
3. Fold the first half of the bottom flap of your helmet base about up 3/4 of the way to the top. Make a second fold where your edges line up with the top part to create the bottom of the helmet.
4. Flip the paper over. Fold the back flap straight up to complete your helmet.