Use a cloth or a towel to clean the surface of the plasterboard as well as the back of the item you will be gluing to the wall. Once the area is clean, apply a layer of adhesive primer to the plasterboard. Allow the primer to dry completely before continuing.
Cut the nozzle of the end of the tube of Gripfill with a pair of scissors. Insert a nail into the nozzle to break the seal inside. Insert the tube into the extruder gun. Place the nozzle of the tube onto the back of the item you are gluing to the plaster board. Pull the trigger on the extruder gun and the adhesive will begin to flow out of the container.
Apply a continuous bead of Gripfill onto the item you want to glue. Continue the bead of adhesive all the way around the edge of the item. Do not allow the Gripfill to go over the edge of the item and do not make the bead more than 1/4 inch in diameter.
Press the object firmly against the plasterboard. Apply continuous pressure for several minutes until the item stays attached to the plasterboard. If you are hanging an item on a vertical sheet of plasterboard, insert nails or pins into it to keep it in place. Do not attempt to move the item for at least 24 hours while the Gripfill dries.