Oh, I love/hate lists like that. They usually seem to have peculiar "must" things that only the author may know about, or care about enough to put on such a list. Some list items are informative, some offer low grade advice, others are WTF?. And in the final analysis what a man (or woman) needs to know is best gathered through a combination of learning and experience for one's own individual situation. Basically, keep your mind as sharp as possible and your body as healthy as possible and what you "must" know will be obvious.
Anyway, I had a revision for
48. Remove a stain. Blot. Always blot.
My alteration, of course, would be, don't bother blotting, get some STPP.