Our ruler is 18" long and 4" wide, and marked in 1/4" increments. You can use any ruler you like for rotary cutting, but the measuring lines are helpful.

As mentioned, we're using an ergonomic cutter with a 65 cm blade.

Almost all rotary cutters come with a "safety". It's usually a button that is pressed to engage the blade. In this photo, the blade is up, tucked into place, and not able to cut anything, including fingers. Do be careful, though, these blades are sharp!

In this photo, the safety is off and the blade is ready to use for cutting. Note how it hangs a little over the edge. Be extra careful at this point.

Have a good pair of sewing scissors handy to cut little bits that the rotary may have missed. We prefer to recut with scissors rather than the rotaty cutter as the rotary blade sometimes cuts more than we mean it to.

Here's our denim. It's nothing special, just a chunk of fabric from the thigh of an old pair of jeans. This could be quilting fabric, fabric for bias strips, or whatever.

For edge 1 - place the denim on the mat, match your ruler edges with the lines on the cutting mat.

Move your hand out of the way, but maintain a firm pressure on the ruler. Engage the blade on the rotary cutter (safety off), and begin to cut along the edge of the ruler ... cut AWAY from your body.

Continue along the ruler (which is being held in place on the guidemarks on the mat).

Continuing to cut away from you, cut through the end of the fabric along the ruler edge. Then remove the cut portion of the denim. Discard.

Leaving the fabric aligned with the mat, move your ruler over 4" (4 marks on the mat). Recall, our goal is a 4" square.

Again, align the ruler with the lines on the mat to assure a straight cut. Cut away from your body, holding your hand clear of the blade of the cutter, firmly keeping the ruler in place.

Remove the now 4" strip of fabric from the ruler's edge.

Turn the fabric 90 degrees and position on the mat such that it is aligned on the mat so we can cut the remaining 2 edges and have a 4" square.

Align the ruler with marks on the mat.

Repeat the cutting process, moving the cutter away from your body. The key is to cut the fabric while keeping the cutter close and sometimes touching the ruler without cutting the ruler itself.

Remove the excess fabric.

Reposition the ruler so that it is 4" (4 marks on the mat) away from the cut line.

Cut away from your body as prior.

Remove the excess fabric and discard.

And now we have a 4" square piece of denim that you can use in a quilt or a wearable art projet. Save up your old jeans and cut them into squares. After a while, you really will have enough to make a quilt top. Keep them in piles of lights and darks, and have fun with the arranging.

Regardless of your use of the fabric that you cut with a rotary cutter, keep safey in mind at all times. Don't become too comfortable with your cutter; remember the safety features it comes with and use them. I had a rotary cutter way back when, got rid of it because I never could quite figure it out, and bought the one you see in this project about 2 years ago. I use it often and wouldn't be without it. It will never replace my scissors, but it's a nice adjunct to have around the house. So, dust off that rotary cutter and learn to use it. Watch those fingers!