Trimming a car mat constitutes a simple process. Since a car mat consists of a rubber side and a carpet side, however, the mat's thickness sometimes makes it difficult to cut without damaging the carpet or the rubber. You'll need a sharp utility or razor knife for this project to work properly. Practice patience during the cutting process, which requires several precise cuts to separate the mat pieces. After cutting the carpet pieces apart, use scissors to clean up the edges and make the sides of the car mat look professionally cut.
Place the mats inside the car. Clean away any large pieces of dirt or objects that stand in the way of the correct fit. Note the areas of the mats that require cutting.
Hold the ruler along the sides of the mat where you want to make the cuts. Draw straight lines on the mats with a piece of chalk to outline the areas that require cutting. Since the chalk will likely come off after moving the mats, work with one cut mark at a time.
Remove the mat from the car, and stick it on top of a large wood block.
Draw the razor knife or utility knife across the top of the mat and the chalk line to score it. Continue to cut along the same line until the pieces fall apart. Cut a small amount of the mat at a time, and progress down the side of the mat until the pieces separate.
Return the mat to the car. Check the fit, and add any additional chalk lines one at a time as needed. Cut the pieces apart using the same method outlined above.
Hold any rough edges of the mat against the sharp edge of the wood block. Trim the rough edges of the mat away with the sharp blade of the utility knife. Trim off any loose carpet threads with scissors.
Return the car mat to the floor and adjust for the best placement. Press the car mat into the floor of the car to keep the mat in place while you drive.
