How to make a three-dimensional cake:

1. Fold the square paper in half and unfold it, leaving a crease.

2. Fold the bottom and top edges of the square toward the crease.

3. Use your hands to unfold the top edge of the square and fold it down along the center line to form an equilateral trapezoid.

4. Use your hands to unfold the bottom edge of the square and fold it upward along the center line to create an equilateral trapezoid.

5. Fold the excess corners inward to make a small square.

6. Fold the two sides of the small square diagonally and unfold it, leaving a crease.

7. Open the small square upward with your hands, fold it inward along the crease, and fold it into a diamond shape.

8. Turn the origami model over and fold the four corners of the square inwards.

9. Fold the four corners of the rhombus inward, and then fold the corners of the rhombus upward again.

10. Use the same steps as above to make another origami model.

11. Overlap the two paper models and fix them with glue. Tips: Please stagger the two models, place them on top of each other, and fold the four corners folded inward onto the other model.

12. Open the eight inwardly folded corners upward and flatten them to form a three-dimensional arch.

13. Take a square that is one-sixth the length of the original paper, fold it diagonally, and unfold it, leaving a crease.

14. Fold both sides diagonally, and fold the small triangle below upward.

15. Use the same method to make 8 identical molds.

16. Fix the 8 triangles vertically on the bottom surface with glue to form a zigzag shape.

17. Take two-thirds of the original square paper and use the method from step 1 to step 9 to make two more models

18. Overlap them and fix them together with glue.

19. Use the method in step 12 to make an arch shape from the inward-folded triangle.

20. Fold the eight corners of the rhombus downward.

21. Align it with the zigzag on the bottom edge and fix it with transparent tape.

22. You can add decorations to the surface according to your own preferences, such as roses, candles, etc.

In this way, the three-dimensional three-layer paper cake is completed.