The rules of etiquette on the right relate to poker played at the real tables but in principle they are also valid for online poker where applicable.
Except for rare cases we do not chat online even when it is allowed.
POKER ETIQUETTE
Act in Turn: Don’t fold
your cards early if you know your hand is worthless. If you act out of turn
and fold, it will have an effect on the betting that would have happened
before your turn. Wait until it's your turn, than fold. This rule also
applies for calling and raising. In short, wait for your turn before you
take any sort of action.
Keep Quiet During a Hand: Regardless of what sort of poker genius you
might think you are, the rest of the table may not want to share your wisdom
during a hand. Also, no hand of poker needs a play by play analysis of each
betting round. This is a distraction to the rest of the players. Save your
commentary for the bar after the game.
Don't Splash the Pot: Keep your chips in a neat pile in front of you
until the time comes for you to calmly place your chips in the pot. Neat
chip stacks help a number of players keep track of what is going on during
the hand.
One Player to a Hand: Poker is not a team sport. If it was there
would be uniforms and butt slapping. You don't get to receive advice during
a hand, and you don't get to give it. Play your own hand and let everyone
else play their own hand.
Pay Attention: If you are going to play, show the game and the
other players the respect they deserve and keep your head in the game so
they don’t have to do it for you.