Heat hide glue in a water bath to 135 degrees F. Here you can see my arrangement. The set-up we use is very simple:

• A simple electric hot plate
• An aluminum can with a tight-fitting top, with a hole cut out for the glue bottle. I fill the can with hot tap water, so I don't have to wait for the hot plate to get it warm. We keep our hot water tap at 150 degrees--kind of dangerous, but we have a small water heater.
• A spice bottle holds a couple ounces of glue--all we need for gluing up one dulcimer
• Inside the bottle is a cooking thermometer to monitor the temperature.
• Also sitting in the bottle is a watercolor brush. I use a selection of brushes for different purposes.

Don't let the glue cook all day--it will degrade it needlessly. Keep the temperature below 150 degrees, especially. Hotter than that will degrade the glue fast.