Widely used by the scientific community, a poster session is a scholarly communication for presenting information from research at scientific gatherings. In poster sessions, large numbers of posters are exhibited simultaneously, usually with the authors of the posters standing by, ready to answer questions.
Posters require even more discipline than other forms of scientific communication beecause of the limited time and space available to catch the audience's attention. A typical poster combines text and graphics, mounted to a bulletin board or wall, in a visually compelling way. Some poster sessions use tables upon which to mount free-standing displays.
Effective posters omit distracting details, long paragraphs of text in tiny fonts, and side issues in order to focus on the main message. Effective posters show clear, striking graphics in full-color, when possible. Text that is borrowed from other scientific literature should be rewritten in a simple, visually attractive fashion, such as bulleted or numbered lists. The sponsoring conference organization will usually provide guidelines for the poster such as dimensions and the times the poster must be attended by the presenter.
A good rule of thumb is this: posters are not upright versions of papers.
Sample poster template by Colin Purrington
Other useful links on poster designing are below: