I look for a PDF version on the manufacturere web site. If none, I scan and make a PDF. Then I store on my pc for easy access. I transfer to my iPad and then i can pull up a manual in the shop when needed. I do that with all my product manual (washing machine....). No more scrounging around for a lost manual.
I keep them all in polythene bag, and that goes
onto the top shelf of a wall cupboard in my shed/shop.
I still have manuals of tools long since gone from my shop..... I don't know why. If I sell a tool I give the new owner the manual for it.