1. Before sticking diamonds, fix each diamond on the canvas with professional adhesive or hot melt adhesive.

2. After sticking the diamond, apply transparent nail polish on the surface of the diamond to prevent the diamond from falling.

3. Double-sided adhesive tape can be used on the back of the diamond picture frame to increase the firmness.

4. If you put the diamond painting in a place where it is easy to be rubbed or hit, you can consider using transparent plastic or glass plate to protect the diamond painting.

It should be noted that the reinforcement method depends on the specific situation. If the diamond painting has fallen off, it is recommended to ask professionals to repair it.