Presented at the 2014 Medical Library Assocation Conference.
This website, created by three American science professors, provides a comprehensive, yet concise, overview of how to create effective posters from defining your message, to planning your poster, to your poster's aesthetics, to how to effectively present your poster during the session. If you are only going to visit one resource on creating your poster, make it this one.
This website, by former evolutionary biologist and current photographer Colin Purrington, reads like a long, humourous, but exceedingly useful essay on poster design, both good and bad. He offers novel ideas for attracting attention to your poster, as well as a number of PowerPoint and OpenOffice poster templates.
Make sure to give credit for images by citing them using the same citation style as the rest of your poster.