The following are my steps to share the manual work of the activity corner:

Step 1: First, prepare a piece of cardboard.

Step 2: Then use scissors to cut out two pieces about 1 cm.

Step 3: Then align the two pieces of paper.

Step 4: Then prepare a pin.

Step 5: Pass through one of the notes.

Step 6: finally, hold one end and move the notes, and a movable corner will be made.