The Ontario Hockey League has been called a goon league because of all the fighting they do. There, it is mandatory players wear a half visor which protects their eyes. If their helmet comes off, they have to put it back on or get off the ice immediately. If they try to push it back on their heads, and move the visor above their eyes, it's a misconduct penalty. Now, if you're fighting a guy with a half visor, the strategy is to give him uppercuts to the plastic first, and then his face. You want to knock his helmet off and then punch at his face.
There is an unwritten rule book of what you can and can't do in fighting, and you'll see all fighters respect this. You fight at the beginning of a shift, and if someone doesn't do anything to you, but your team is losing and not playing hard, you find the other team's goon, and you both agree to fight to get your teams motivated. Another thing, you'll see this a lot in the NHL. If after fighting a while, two guys get tired, they mutually let go of eachother, and just turn to the penalty box. There are fights where the linesmen step in (after a while), and there are fights where the linesmen approach when the two fighters get tired, and just skate with them to the penalty box. You only punch to the head, you never punch below the chin. The skull protects the brain, but there are vital organs down below. Besides, some goons say (probably because they've hit their heads too many times) that women love scars. You never fight a guy who doesn't want it. He could be injured or tired and not ready to fight. Unless he seriously injured one of your teammates in which case it's revenge. A big guy rarely challenges a small guy. However, small guys challenge big guys a lot. Eric Lindros, 6'5", 235 lbs., will not challenge Theo Fleury, 5'9". But Fleury can challenge Lindros. Goalies do not fight unless it's an all-out brawl, in which case the goalies will fight eachother. Ron Hextall and Ed Belfour are two experts in this field, though Hextall had the tar beaten outta him by Felix Potvin once.