The following video from Laura at SewVeryEasy offers some wonderful tips for speeding up the process of drawing lines on fabric. These work especially well for half-square triangles. They also work, with a little adapting, any time you need to draw on fabric.
If you’ve been quilting for awhile and have developed your own process, you may be tempted to skip the video. We encourage you to watch anyway as there are some great ideas here that you may not have considered.
Note: Laura uses the Little Gripper from Gypsy Quilter (get it here). This works great with small rulers. Larger grippers are available for larger rulers.