My favorite solution is to keep something (preferably a metallic something!) between the blade and the fingers. That may include (but is not limited to) a framing triangle, spring clamp or piece of angle iron.
I have found a small plastic cutting board (one of my wife’s kitchen rejects) very useful for cutting wood and plastic stock. A little practice on pieces clamped between the cutting board and the framing triangle will result in straight square cuts in the stock - and none in the epidermis.
I have also chosen to make much more use of a hobby saw, and a lot less use of anything with an unshielded blade. Arthritis is not conducive to fine tool control!
Chuck (modeling Central Japan in September, 1964)