Please watch where you walk. Not everyone can fit in the seats and there may be the odd foot or knee sticking out from the seat. You need to watch for it.
If you have a backpack, take it off your shoulder/back. The last thing anyone wants is a swinging backpack to the head.
If you get on the bus and there are no empty seats left, don’t stand by the front door; move to the back. Don’t make other passengers work their way past you while they try to get to the back.
If your getting off at the next stop or even the one after and the bus is filling up, give up your seat to someone else. It’s inconvenient for you to expect everyone to move out of the way and for the bus to wait while you wiggle your way to the door.