The following websites should help you get started.
- “Preparing an effective poster” by Seri Rudolph of the Writing Workshop (http://abacus.bates.edu/~ganderso/biology/resources/making_posters_2004.pdf)
- Poster-making 101 by Brian Pfohl in Psychology (http://abacus.bates.edu/~bpfohl/posters/)
- Poster mechanics specific to the Mount David Summit (http://www.bates.edu/poster-mechanics.xml)
- From the Association for Women in Mathematics, pictures and details from some past posters (http://www.awm-math.org/workshops/posters.html)
- At North Carolina State University, check out Creating Effective Poster Presentations, written by Hess, G.R., K. Tosney, and L. Liegel. 2006. (reference added to this Bates Math FAQ page March 2010)