What is an alternative to blutac that doesn't leave marks?

An alternative to Blu Tack that doesn't leave marks is double-sided tape, specifically removable or washaway varieties. These tapes provide a strong hold without damaging surfaces and can be easily removed without residue. Another option is adhesive putty designed for use on walls, which is formulated to be less sticky and less likely to leave marks when removed. Additionally, reusable silicone adhesive strips can also be effective for similar applications without causing damage.