Identify the type of glue
Check the glued material for heat or solvent sensitivity
Soften with warm water if the glue is water-based
Apply rubbing alcohol or acetone if the material can tolerate it
Use a commercial adhesive remover for stubborn residue
Gently scrape with a plastic scraper or credit card
Peel apart slowly while the glue is softened
Reapply heat with a hair dryer for heat-softened adhesives
Wash the area with soap and water after removal
Test any solvent on a hidden spot first