1, take a relatively new deck of playing cards first.

2. Take out two playing cards. The bottoms of the two cards are about 5 cm apart, and the tops are together to form an inverted "V" shape.

3. Put a small triangle beside it, and the distance between them is about 1cm.

4. Take a card and cover it on two small triangles.

5. Put a small triangle on the card surface just covered horizontally, so you can set up two layers.

6. Add a small triangle next to the bottom triangle and follow the previous steps in turn.