Hi, I'm Bill Walker and I'm here to show you how to cut window blinds. You will need a measuring tape, a marker and a hacksaw. The first step is to measure the inside of the window sill. Using the tape measure, measure the width of the top of the sill. Now measure the center and lastly measure the bottom. With a pencil, mark down the smallest of these measurements. You will need an eight inch leeway on each end of the blind. Subtract a quarter inch from the width of the blind and this will give you the eighth inch leeway that you need. Next you are going to use this measurement to determine how much to cut off the blind. Take the measurement tape and mark the spot on the headrail where you will cut the blind down. Take the hacksaw and saw off this portion of the headrail. If the slats are too wide, you will have to do the same procedure and cut each slat and you will have to do the same for the bottom rail. And that is how to cut window blinds.