Mirrors have always been popular wall decorations. They give you a place to check your reflection, allow you to see around the corner and into another room and generally make the room feel bigger. Redecorating your home may make a mirror too large for your new space. Instead of purchasing a new mirror, you can cut the mirror you already have to make it fit the size and shape you need. Since mirrors are basically glass with a reflective backing, you can cut them with a diamond-tipped wet saw blade.
Stretch the tape measure across one side of the mirror. Place a dot at the appropriate measurement. Mark the opposite side of the mirror with your fine-point marker.
Stretch duct tape between the dots. Press the tape firmly against the mirror. Place another piece of tape parallel to the first, leaving a 1/8-inch gap between them where the cut needs to be made.
Turn on the wet saw and let the blade come to full speed. Push the mirror slowly into the saw, keeping the blade between the pieces of tape.
Remove the tape from the finished piece of mirror. Spray window cleaner onto the mirror. Dry with paper towels.