Watercolor Paper
How do I prevent watercolor paper from rolling up?

I have 140 lb watercolor paper, but when it is painted on, it curls up like an upside-down arch. How can I keep it flat without damaging the painting or paper? Thanks in advance!

Tack or pin it to a board – pre-prep the paper: http://search.yahoo.com/search?ei=UTF-8&fr=ush-ans&p=prepare+watercolor+paper+for+painting

How to Stretch Watercolor Paper