Things You'll Need
Removable adhesive strips
Removable picture hangers
Lathe and plaster walls were a very common occurrence in homes built prior to 1920, and even in some homes that were built later on. While plaster is very hard and durable, this can work against you when trying to hang artwork or posters. The usual technique of pushpins or scotch tape will not work in this instance. However, there are two ways that you can hang a poster on a lathe and plaster wall without ruining either one.
Lay the poster, face side down, on a flat surface. It is easier to work with the poster if it is on a sturdy surface.
Cut small squares out of removable adhesive strips. You will need eight squares total, or 12 if the poster is quite large. The adhesive must be removable or you will have a mess on your hands if you ever decide to remove the poster.
Stick the squares into each corner of the poster. Gently push one square into each corner of the poster. Line them up so that the adhesive is not visible. Put more adhesive squares between the top two corners, the bottom two corners and on the side edges.
Affix the poster to the wall. Pick the poster up by the top, center it and gently press the spots that have the adhesive strips onto the wall. Work slowly and make sure the poster is level.
Frame the poster. Alternatively, you can frame the poster and then affix it to the wall with removable adhesive picture hangers. You could also attach a masonry bit to a drill, drill a small starter hole in the wall, and then use a masonry screw to hang the framed poster, particularly if it's heavy.