How do you attach paper to a wall without damaging it?
Keeping this in view, how do you glue paper to a wall?
Roll a thin layer of Mod Podge on the wall, working in a section that is roughly equal to the width and length of the newsprint. In other words, if your newspaper is 3-by-2 feet, spread glue on the wall a few inches beyond this dimension to keep a wet edge, just as if you were painting the wall.
Moreover, how can I hang a poster without damaging it?
Put tape on the front of the corners (all the way to the edge) and then tape it to the wall but put the tape over your "laminated" corner. Use magnets. There are some strong magnetic poster hangers that hang posters without damaging them.
If the paint on your walls is too thin, it may peel off with the Blu Tack, and if the wall surface is at all porous, oils from the adhesive can seep into it. Careful cleaning can generally take care of these blue stains and leave the walls unblemished.