On posters, graphs are better than tables. There is not much that can be presented in a table that cannot be presented in a graph.
If you feel you must use a table for some reason, check these tips at In the Haystack.
Like me, author Boris Gorelik is fond of rules of two.
Photo by oskay on Flickr, used under a Creative Commons license.
Edward Tufte on Data, Analysis, & Truth
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