Being a goalie doesn't mean just trying to stop the puck. It also means you need to communicate with your teammates. By communicating with your teammates, your team will have a great advantage in your own zone especially. By communicating you will let your teammates know where the puck is or who is pressuring them when they go behind the net to retrieve the puck. It's very simple.
You can communicate in many ways. When the other team dumps in the puck and they have pressure, I will yell "Man on man on" and if there is no one then I will yell "Time, time". If a player from the other team or your team gets out of the penalty box, slap your stick on the ice to let them know he is out. By doing just these little things you can really help out your team a lot.