What is Proper Trade Etiquette?

New to trading, using the site to find an item but no one responds to any of my whispers.

A friend of mine taught me how to set up and use a trade stash spot and the site but like I said, I'm getting nothing from players, when when they list an item ("posted x seconds/minutes ago") so am I doing something wrong here?

People aren't necessarily just waiting in their hideout for trade offers.
Even if they do that sometimes, they still play the game.
The people you're whispering are in a map, fighting a boss, halfway through a trial, and might not even notice they received a whisper.
Or they were whispered by 10 people and you weren't the one they clicked.
Or they were whispered by more people and went "hmm, I should sell this for more, I'm going to go raise the price now"