How can I preserve MDF pattern templates?

I was planning on storing the MDF templates for an Adirondack chair in my garage attic, but realized the humidity may warp them. How do you preserve your templates? These have photocopied patterns glued to one side.
—James Kahl, Edgewood, Maryland

Because MDF has no grain, it is largely unaffected by changes in humidity, Jim. Unless you fear that water will drip directly on the templates, simply store them flat or drill a hole and hang them from a rafter. This prevents them from distorting under their own weight.

Sealing the patterns with a clear finish provides some protection from wear and tear, but the photocopied patterns may smear photocopier toner when you brush a finish on.

Instead, spray on a clear finish and don't touch the pattern lines or text until the finish is dry.