Wipe the area that has the dent/ding with 91% or higher alcohol. As you clean the area, the cloth you are wiping will start grabbing the surface.  Choose the appropriate glue tab. Typically, you should use a tab that fits within the outside edge of the damage. you want to pull from the center of the dent.  Apply hot glue to the tab's flat surface. You will want to use enough so when you place the tab against the area some of the glue flattens tot he sides. Leave about 2mm between the tab and the surface.  Place tab into middle of damage. Press until you think there is about 2 mm of glue between the tab and surface.  Allow glue to set up.  Place your slide hammer (or whatever glue pulling tool you will use to pull) in place. Once there, make your pull.  The tab should make a "pop" sound. Remove excess glue with 91% or higher alcohol.  Check results. Repeat until damage is removed to satisfaction.