It is important to know if you were able to read it and if you remember what was written or drawn; there lies the key for the interpretation of the dream. Sometimes the unconscious uses word play and phrases to tell you something.
If an image is displayed instead of words it is necessary to consult its symbolism. Other symbols and the oneiric scene context are also important for the correct interpretation of the dream. [1]
If your name is on the poster: you have behaved badly in a certain matter and others will expose you.
Depth Psychology: The poster usually announces news, sometimes even excitement.
See also: Advertising, Newspaper. [2]
A poster can also represent aggrandizement, idolization and that you’ve put someone on a pedestal that you see as larger than life.
If you dreamed of putting up posters, take great care not to rush into anything new without thoroughly checking it out. [4]