Open the door, and swing it to the area where you want it to stop. Use a pencil to mark the location on the floor by the side and front edges of the door.
Measure 2 inches from the front edge of the door, and make another mark. Measure 1 inch to the side of this mark, and make a third mark. Ensure that the mark is on the side of the door that swings into the room.
Create a hole on this spot for the door stopper. Punch the hole with an awl if you have a floor made from a relatively soft material, such as wood or laminate, and use wood screws to screw in the stopper. Alternatively, drill the hole into the floor if it is made of a hard material, such as cement or tile. Insert a fiber filling into the hole before screwing in the stopper. Ensure that the cushioned section of the door stopper points toward the door to prevent possible damage on impact.