Take a square piece of paper and fold it into a straight line from one corner (as shown in Figure 1- Figure 2).

Fold at right angles from the right to the left along another corner (as shown in Figure 3- Figure 4).

Fold 30 degrees to the left along the other corner (as shown in Figure 5).

Fold from top right to bottom left (as shown in Figure 6).

Finally, the upper part is nested downward in the double-layer part (as shown in Figure 7- Figure 8).

The effect diagram is as follows:

end

Matters needing attention

The folding angle can be adjusted according to the paper size.