The blog "Put This On" has a list called "Twenty-Five Pieces of Basic Sartorial Knowledge So You Don’t Look Dumb." Sadly, most men I see today need at least some of these. It's astounding how quickly this knowledge has been lost; I believe it was basic, common knowledge just a couple of generations ago.
I enthusiastically agree with 23 of them.
The two exceptions:
"20. Never wear visible socks with shorts."
I don't have a strong opinion either way; I generally see shorts as utilitarian and inherently unstylish, and the bare male leg as unattractive.
"Never wear polyester outside of the gym or theme parties."
Polyester isn't ideal. But, in my opinion, cotton-poly shirts that still look and basically feel like 100% cotton, or silk-poly ties that still look and basically feel like 100% silk, aren't deal-breakers.
Regardless, this is probably the best and most succinct list of basic sartorial rules I've ever seen. I wish every man would read and internalize it.
I reproduce it below, in case it's ever removed:
1. Unbutton the bottom button of your jacket. It’s not intended to be buttoned.
2. Same goes for your vest.
3. Remove the tags on the sleeves of your jacket before you wear it.
4. Jackets sometimes come with white basting thread on their shoulders
or holding closed their vents. Remove this thread before wearing the
5. Jacket pockets are intended to be opened. Use a small scissor or seam ripper.
6. More than three jacket buttons is never appropriate for anything.
7. On a three-button coat, buttoning the top button is optional, and some lapels are rolled so as to make the top button ornamental. In other words: if buttoning the top button seems wrong, it is.
8. Brown shoes, brown belt. Black shoes, black belt.
9. Belt or suspenders. Never belt and suspenders.
10. Your jacket sleeve should be short enough to show some shirt cuff - about half an inch.
11. Your pants should end at your shoes without puddling.
A slight or half break means that there is one modest inflection point
in the front crease. If your pants break both front and back or if they
break on the sides, they’re too long.
12. Your coat should follow and flatter the lines of your upper body,
not pool around them. You should be able to slip a hand in to get to
your inside breast pocket, but if the jacket’s closed and you can pound
your heart with your fist, it’s too big.
13. When you buy a suit or sportcoat, it should be altered to fit by a tailor. This will cost between $25 and $100.
14. Your tie should reach your belt line - it shouldn’t end above your belt or below it.
15. Your tie knot should have a dimple.
16. Only wear a tie if you’re also wearing a suit or sportcoat (or, very
casually, a sweater). Shirt, tie and no jacket is the wedding uniform
of a nine-year-old.
17. The only men who should wear black suits during the day are priests, undertakers, secret agents, funerals attendees and yokels.
18. Cell phone holsters are horrible.
19. So are square-toed shoes.
20. Never wear visible socks with shorts.
21. Or any socks with sandals.
22. If your shirt is tucked in, you should be wearing a belt (or
suspenders, if you’re wearing a jacket as well, or your trousers should
have side adjusters and no belt loops).
23. Flip flops are great for the pool and the beach and not great for
anything else. (Some say this is a matter of taste. We agree. If you
have any taste, you will only wear flip-flops at the beach or pool.)
24. Long ties are not appropriate with a tuxedo.
25. Never wear polyester outside of the gym or theme parties.