Rough Draft
Try to produce a full size rough draft in advance to catch any unforeseen errors.
Only print a miniature version of your poster on letter sized paper to get a very rough sense of layout changes.

Peer Revisions
Ask friends to critique the full size rough draft while you are not present. Using Post-Its that you provide, ask them to comment on the following:

• Word count
• Prose style
• Flow
• Figures
• Font size
• Spelling