1. Take a piece of paper, then use a ruler to draw four straight lines, and then cut them along the straight lines.

2. Cut a small strip, then make four corners for it to make a square, then fold a small corner and stick it up.

3. Then write happy birthday on the paper just now, draw a cake, then color it and cut it out.

4. Then find a new piece of paper and stick the square on a place you like, and then stick the happy birthday and cake on it with glue or double-sided tape.

5. Then make some decorations you like on the greeting card, and the greeting card is complete!