Put a self-adhesive one-way door tent easily by following these steps. First, get all materials: the tent film, a cleaning spray without ammonia, a utility knife, and a squeegee. Clean the window well to remove dirt and dust. Make sure no scratches are on the glass. Measure the window size carefully. Cut the film with an extra inch to trim later. Spray water on both the glass and film to keep it wet. Place the film on the window, matching the edges exactly. Use the squeegee to push out air bubbles and water. Cut off any extra film around the edges. This method helps the tent stick smoothly and last longer. Small care steps make a big difference in the final look.