I have a section on my bookshelf for my collected reference materials. I'm not talking about reference books. I have a whole set of three ring notebooks that contain leaflets, pamphlets, printed out pages, handouts from classes, and the instruction sheet(s) that I got when I purchased the whiz-bang gadget of the week to make crafting easier. I've got a notebook on machine embroidery stabilizers and another one on hand embroidery fabrics. I've got at least one notebook for each of my sewing machines.
Yes, I use the information in these notebooks. I can't keep it all in my head. There are days that I think I'm doing well to remember that I wrote that information down once upon a time.