Origami sheet - pants :

Step 1.

Take a square sheet, lay it flat on the table, with the bottom edge horizontal.

additional information

If it is two-colored, place the colored side against the table.
The corners of the square are: top left, top right, bottom right, and bottom left.

Step 2.

Make a vertical valley fold by bringing the right edge over to the left edge.

Crease well and leave folded.

additional information

You get a double-thickness rectangle in vertical position.

Step 3.

Make a horizontal valley fold by bringing the bottom edge up to the top edge.

Crease well, then unfold.

Step 4.

Make a vertical valley fold by bringing the right edge over to the left edge.

Carefully crease the fold and then unfold.

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We have just marked the vertical axis of symmetry. It is a valley fold.

Step 5.

Create a vertical valley fold by bringing the right edge from right to left along the valley fold marking the vertical axis of symmetry.

Firmly crease the fold through both layers and let it fold.

Step 6.

Create a vertical valley fold by bringing the left edge from left to right along the valley fold marking the vertical axis of symmetry.

Firmly crease the fold through both layers and let it fold.

additional information

We obtain a vertical rectangle with, at the front, two free rectangular flaps of double thickness (one right and one left), each attached to the base rectangle by a hinge edge.
The junction of these two sections forms a slit along the vertical axis of symmetry.

Step 7.

Using the valley fold along the vertical axis of symmetry, fold the right part of the fold over onto the left part.

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The folding is a narrow rectangle in a vertical position, with a hinge edge on the right.

Step 8.

Rotate the folding onto itself so that the hinge edge becomes the horizontal bottom edge.

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In the middle of the fold, there is a mark corresponding to the vertical axis of symmetry.

Step 9.

Starting from the middle of the hinge edge, make an oblique valley fold by bringing the right part of the hinge edge along the vertical axis of symmetry.

Firmly crease the fold through all layers and let it rest folded.

Step 10.

Starting from the middle of the hinge edge, make an oblique valley fold by bringing the left part of the hinge edge along the vertical symmetry axis.

Mark the fold well through all layers and allow it to fold.

additional information

The folding is now a pentagon.

Step 11.

Transform the two previous oblique folds into inside reverse folds.

additional information

The overall shape of the folding is a pentagon.
The right part and the left part of the folding are vertical four-panel double-thickness accordions.
A vertical slit separates the two accordions.
The front lower part and the back lower part correspond to two triangular pockets whose openings are horizontal on the 12 o’clock side.
One can also say that there is a front right flap, a back right flap, a front left flap, and a back left flap.

Step 12.

Flip the front right flap onto the front left flap.

Step 13.

Turn the folding from right to left.

Step 14.

Flip the front right flap onto the front left flap.

additional information

The front and back faces all become smooth.
The folding is a pentagon with a vertical left edge, a horizontal top edge, a vertical right edge, and two slanted bottom edges that meet at the bottom point.

Step 15.

Along the imaginary horizontal line connecting the lower left corner and the lower right corner of the pentagon, make a horizontal valley fold by bringing the top part of the front flap down over the bottom point of the fold.

Crease well and let it fold.

Step 16.

Turn the fold over from right to left.

Step 17.

Make a horizontal valley fold by bringing the top edge of the fold down to the bottom edge.

Crease well and let it fold.

additional information

The fold is a vertically positioned rectangle composed of:
A rectangular front flap in a vertical position, with a slit on the ceiling side.
A thick middle triangular flap, with the free tip oriented at 6 o'clock. This middle flap resembles a water bomb base.
A rectangular rear flap in a vertical position, with a slit on the tabletop side.
One can also say that there is a right front flap, a right rear flap, a left front flap, and a left rear flap.