Steps:

1. First, fold the square paper diagonally corner-to-corner to make an X shaped crease on the paper. 

2. Then, cut the four diagonal lines starting from the corner going up halfway to the center of the paper.

3. After that, punch a hole into the center and nearby every other end of the paper.

4. Gently fold the corner points with punched holes and glue them to the middle of the paper. 

5. Punch a hole into the center of the circular paper. After that, glue the circular piece of paper on top of all the corner points. 

6. Later, thread the pipe cleaner through the hole and roll one end of the pipe cleaner to prevent it from coming off the pinwheel. 

7. Next, put the pipe cleaner into the straw at the bendy side. Wrap the loose end of the pipe cleaner around the straw. 

8. Finally, bend the straw. The pinwheel is finished!