1. Use E6000 glue: Apply E6000 glue to the primer of the diamond painting, and then stick it on the canvas until it is completely dry.

2. Use hot melt adhesive: After heating the hot melt glue gun, apply hot melt adhesive on the primer of the diamond painting, then stick it on the canvas and wait for it to dry completely.

3. Use double-sided tape: stick the double-sided tape on the primer of the diamond painting, and then press it on the canvas until it is completely dry.

It should be noted that before using the above method, it is best to clean the diamond painting primer and canvas to ensure better adhesion effect. At the same time, we also need to pay attention to the safety problems when using glue to avoid glue sticking to other places.