Every origami folder, no matter how skilled, sooner or later comes back to the same handful of foundations. The Square or Preliminary Base is the most famous of them all, the quiet starting point behind the crane, the lily, the waterbomb and a surprising share of everything else you have ever folded. What makes it so appealing is how little it asks of you: two folds in half, one flap lifted, a careful squash-fold, and the same again on the other side. The whole sequence takes less than a minute, yet it gives you the classic square-with-an-open-point shape that so many models grow out of. It is the kind of move worth learning perfectly, because you will use it again and again for the rest of your folding life. Grab a square and let us make the base of bases.

This is probably the most common base in origami and is used in many different models. Sometimes this base is called a Square Base and sometimes it’s referred to as a Preliminary Base.

Step 1

Start with a square sheet of paper with the white side up. Fold it in half along the dotted line.

Step 2

Fold the paper in half again along the dotted line.

Step 3

Bring the top flap of paper up.

Step 4

Squash fold this flap of paper down. Make sure you keep both sides symmetrical. You should end up with a diamond shape.

Step 5

Turn the model over.

Step 6

Lift up the top left flap of paper to the middle.

Step 7

Squash fold this flap of paper down. Make sure you keep both sides symmetrical. You should end up with a diamond shape matching the one on the other side.

The completed Square or Preliminary Base.