To attach Christmas lights to windows, use adhesive clips or suction cups designed for windows. Start by cleaning the window surface to ensure good adhesion. Place the clips or suction cups in a pattern around the window frame, then secure the lights in place. Make sure the lights are evenly spaced and avoid overloading electrical circuits. For a neat appearance, use a light gauge extension cord to connect the lights to a power source.

Attach Christmas lights using adhesive clips or suction cups, ensuring the window is clean for good adhesion. Space lights evenly and avoid circuit overloads. Use a light extension cord for a neat setup.