Common errors:
This information is from the Medical Anthropology students from the first semester for a cheap way to print posters. Evidently, you have to have a Taobao account to access the site: http://e22a.com/h.bcJCOr?cv=AAOsANLS&sm=c2dbf0
No endorsement given for this site but it is just offered as an alternative.
Useful websites about how to create an effective poster