Things You'll Need
ruler or measuring tape
strip of cardboard
For latch hook enthusiasts, yarn comes in all colors and varieties. Most latch hook yarn comes pre-cut from the manufacturer; however, using this type of yarn can limit you to the specific colors and fibers that the manufacturers carry. If you cut your own latch hook yarn instead, you can use any fiber and color that you desire.
Cut your own Latch Hook Yarn
Determine the number of holes to be used. For example, if you are going to use red yarn over one specific area of your latch hook design, then you need to know how many holes are in that area. You can count them yourself or you can multiply the number of holes in the width by the number of holes in the length. To do this for larger areas, you may need a calculator.
Decide how long you want your yarn to be. Pre-cut yarn generally comes in 2 1/2 inch lengths, but you can use whichever length you like. You may want to experiment with different lengths in your latch hook to decide which ones you like best.
Determine how much yarn you will need. One yard of yarn is 36 inches long; if you are going to cut your yarn into 3-inch segments, then you will get 12 lengths of yarn out of every yard. You already know how many lengths of yarn you will need from step 1, so now you can figure out how many yards you will need in order to yield the appropriate number of yarn segments.
Create a cutting device; Bellaonline.com shows a simple way to do this. Get a strip of cardboard that is six inches long and as wide as you want your yarn lengths to be; for this example, we will say that the cardboard needs to be six inches long and three inches wide. Fold the cardboard in half lengthwise, so now you have a piece of cardboard that is three inches by three inches in size. Put a pencil into the cardboard fold lengthwise.
Wrap your yarn around the cardboard. Wrap gently so that you do not stretch the yarn too tightly; otherwise it will be shorter than three inches when you cut it. Wrap the yarn in a single row all around the cardboard device, looping the yarn around until you have covered most of the cardboard.
Cut the yarn. Insert your scissors into the open edges of the device and cut the yarn on both ends. Now you will have several lengths of yarn cut to three inches apiece. Repeat this as many times as you need in order to get the desired number of yarn segments for your project.
Practice cutting a few lengths of yarn with your device first; measure them to be sure the length is accurate.