“Its basic manners that I know a lot of people dont follow.”
This Redditthreadis filled with people sharing those rules.
Here is what some of them are:
Note: Some responses have been edited for length and/or clarity.

Instead, stand on the same side, so people can easily pass."
do NOT greet them with a ‘to-do’ request or some sort of reminder.
It’s a universally shitty feeling to be greeted by that."

u/believe0101
3.
“You having a bad day doesn’t mean that you have to ruin other people’s day.”
I can have a bad quarter or even two quarters without a fully ‘bad day.'"

u/katskratched
4.
“If you open something, close it.”
u/RiseinAshes
6.

“Let people get off the elevator, bus, whatever before you shove your way on.”
“You remember far more embarrassing moments about yourself than your environment remembers about you.”
u/Do_Not_Touch_BOOOOOM
8.

“Most of our learning comes about through making painful mistakes.”
u/fermat9997
9.
Not everyone is as interested as you are in your favorite topics.
“Secure your own oxygen mask before helping others.
Take this bit of advice and carry it whatever you go through.
u/Naturage
11.
“Wipe down the damn sink when you’re done.”
u/funkybaconburger
12.
“If you want to listen to something in public, use fucking headphones.”
“Greeting your coworkers when you arrive at work.
Its basic manners that I know a lot of people dont follow.”
u/Maleficent_Nobody_75
14.
“Give a little wave of acknowledgment when someone lets you merge or join the stream of traffic.
Flash your lights if there are cops up the road.
(Or pat the top of your helmet if you’re riding a moto).”
u/Dexember69
15.
“Your lack of preparation does not equal someone elses emergency.”