A ruler of thick, clear plastic used to make straight cuts with a rotary cutter. Available in a variety of sizes and shapes.

There are several different brands of rulers, for example OmniGrid and O'Lipfa. A distinguishing characteristic among the brands is the color of the gridlines. Try some different rulers before purchasing so that you find the ruler that works best for you.

Any other tips you have on creating straight lines? Add your tips by using the EasyEdit button.