To create a 3D greeting card, you can follow these steps:
1. Choose a thick cardstock paper for the base of your card.
2. Cut out two identical shapes (such as hearts, stars, or circles) from colored paper or cardstock.
3. Fold each shape in half vertically down the center.
4. Attach one half of each shape to the front of the card, making sure they align perfectly.
5. Attach the other halves of the shapes to the inside of the card, creating a 3D effect when the card is opened.
6. Add decorations, such as stickers, glitter, or ribbons, to personalize your card.
Here is a simple example using ASCII art:
```
_______
/ /\
/ / \
/______/____\
| |
| Happy |
| Birthday! |
| |
\ /
\ /
\________/
```
