•Tools required: Electric drill, iron saw or chainsaw, measuring ruler
•Step1: First draw the dimensions of the door cover with a piece of paper (there may be a few millimeters of error).
•Step2: The drawing makes good compare on the door is good, draw good mark with pencil.
•Step3:The 4 corners of the door that draw good drill a hole firstrespectively, begin to dig a hole directly if have electric saw next.
•Step4: If it is a glass door, use a tool to scratch the glass, gently scratch it open and fix it with glass glue.
•Step5: The hole was pulled out, do a layer of wood skin to wrap around the hole first now, for beautiful.
•Step6: Install cat door, have accessory screw, screw with screwdriver.
•Step7: Screw mouth still has screw cover, it is ok to press.