One should remember that the pole is for holding only
Don’t hug it, lean on it, interlock your arm around it, or even dance on it (yes, “It’s Showtime” guys, if the subway is crowded, that means you too).
One should not use an entire seat for his or her belongings
Does your bag have a person in it? Good, now put it on the floor. Or hold it. Just get it the hell off of the most sought-after real estate on the train.