This information was shared by Diane Crothers as part of the Lightbulb Night program in October 2018.
The Learn How to Quilt website has a very good video about sewing partial seams.
For sewing Y-seams, The Fat Quarter Shop has an excellent video by Edyta Sitar. Edyta doesn’t even mark her stopping points, but you can. Using your quilting ruler mark the 1/4” intersections as you see in the image below.