How can I remove a smear of glue from a hot glue gun from denim?

You will be able to get some of it off by ironing it onto a small stack of paper towels. Sometimes freezing it with ice will allow you to peel it off. If a sticky residue is left, use Goo Gone, a commercial product available in sewing stores and drugstores.

Sharon Stevens, HES Extension, College of Human Environmental Sciences,
University of Missouri-Columbia