What is the best way to make folders for home filing?

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Neither of these describe how to make the file folders themselves. I'd say you can use cardboard pieces sized to letter or legal size. Think the back of a writing pad, not a corrugated box kind of cardboard. You want it to be stiff, yet not bulky. Glue some fabric or heavy paper along the bottom long edges and part of the sides to make a pocket. The advantage of this is you can make it as wide as you need to. For the hangers at the top, you can either recycle old metal bars from worn out folders or make your own with skinny dowels. Again, take some fabric, attach one end to the inside top of your "folder", wrap the dowel/metal and attach the other end of the loop just below your previous attachment. You may want to use staples or brass paper fasteners to make it a little sturdier if it's going to be heavy. You can then paint or decorate with fabric/paper to finish it off and cover over any sharp things. You can buy stick on tabs for labeling or make your own out of cardboard, small bits of plastic (maybe old credit cards?), etc.

If you have a printer with a scanner, save it to your computer. Or take a picture with your phone and send yourself an email. Folders take maintenance and time. Just remember to back up your computer.

You can buy a pack of manilla file folders at the Dollar Tree for a buck., You can also use one of those plastic cubes with hanging file folders to make an inexpensive filing option. Most of the cubes you buy have a plastic runner inside on 2 sides that perfectly fit a hanging file folder. Sometimes I see a pack of these in thrift stores too.