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Once the adhesive has had sufficient time to soften and shows signs of loosening (it may appear bubbly, gel-like, or lift easily at the edges), use a plastic scraper or a dull putty knife. Hold the scraping tool at a shallow angle, almost parallel to the wall surface, and gently push and lift the softened residue away. Work in small, manageable sections, taking care not to apply excessive pressure that could gouge, scratch, or damage the underlying wall material (paint, drywall, plaster). Repeat this process until the majority of the adhesive has been removed.