A few products used to attach posters to walls, like thumbtacks or putty, damage the paint. When the poster is removed the wall has to be touched up or repainted. A two-sided adhesive tape works best for hanging posters without ruining the paint job. The type of paint sheen on the wall will determine the strength of adhesive. There are low-, medium- and high-strength adhesive tapes. A low adhesive can be used on flat and eggshell paints, medium-strength adhesives will work on satin paint, and a high-strength adhesive can be used on semigloss or high gloss.
Inspect the paint on the wall to determine what sheen or lustre it is. If there is no reflection, then it's a flat paint. If it has a hint of a reflection, then it's an eggshell. If has a dull reflection, then it's satin paint. If you can see blurring shapes of the things in the room reflecting in the paint, then it's a semigloss. If you can see your face in the paint then, it's a high gloss.
Place the poster face down on the floor.
Pull the waxy paper off one side of four pieces of adhesive tape and stick them to the corners of the poster.
Remove the waxy paper from the two-sided tape in the two top corners and then stick the poster to the wall.
Lift the bottom corners of the poster up and pull the waxy papers off the tape. Stick these corners to the wall.
When you remove the poster, grip one of the corners and slowly peel it away from the paint using one consistently tensioned tug. If any adhesive is left on the paint, scrub it off with cotton balls and rubbing alcohol.