• Test your setup! It sounds obvious, but it’s vital to make sure you have Mumble configured for the optimal audio fidelity, as everyone will be listening to you. Even if you normally use voice activation, it may be worth switching to push-to-talk for commentary.
• Use QTV, not Spectator. This ensures that you will be (roughly) synced with the observers
• Don’t be afraid to make bold predictions; people would rather hear you voice an opinion and get it wrong than simply sit on the fence not really saying anything.
• In my opinion, commentary duos work best with a ‘straight man’. That is, there is one guy doing most of the work while the other guy just chips in by correcting mistakes, prompting with questions or offering their view when asked. This is pretty much how soccer commentary works, at least here in England. If you have two guys trying to comment on the action at the same time it rarely works. Consider switching roles between maps
• Try to voice the countdown as this helps to sync recordings with demos.
• It’s generally best to stick with autotrack POV, as again this helps to keep observers synced.
• If you do choose to manually switch POV, make sure you announce it so everyone can switch. Try to avoid constantly changing POV.
• Nowadays during QTV playback there are a lot of aids to update you on the game situation, like the count of RLs on each team, moreinfo notifying itemspickups, teamoverlay, radar etc. While all the observers can see this, there’s no harm in occasionally stressing key changeovers as this may help less experienced 4on4 players appreciate the crucial moments in the game.
• ‘Colour commentary’ can be a good way to break up functional, and dare I say it perhaps rather mundane commentary. If there is a particularly funny or tense moment, throwing in a “WHOOOA!” or “OH. MY. GOD!” can build the shared experience with the observers. Just don’t do it after every fight. If you think a player just did something particularly dumb, don’t be afraid to say so (they can’t hear you!).
• Rather than simply vocalising what everyone has just seen, try to put yourself in the head of the player you are watching. Interpret the game situation and offer insight as to what you think the player will or should do next. For example, if a player is on a quadrun think about where he might want to attack next, or maybe let people know that an important item like Pent or RA is spawning soon in case he is going to secure that.
• 99% of game situations will have been experienced in one form or other by the observers. So you can all empathise with how a player might be feeling when he gets teamkilled by a greedy frag-chaser, is desperately roaming the map in search of rockets, or pulls off an amazing pent steal from under the noses of a fully stacked opposing team. If you talk emotionally about such situations, it can help build a rapport with your audience.
• Acknowledge the fact that not every game with be a close, nailbiting encounter decided by a quadbore in the final minute. If one team has an unassailable 100+ frag lead with only a few minutes remaining, it’s OK to stop commenting on the action and instead reflect on the game as a whole. What where the crucial moments? Do you think any player played particularly well? Also muse about what’s coming next, i.e. what map will be chosen, will the lineups change, how the result will affect the league table or who the winner meets next in playoffs etc
• Don’t trash-talk, that’s not why you’ve been given the stage. It’s fine to criticise mistakes by players but never make personal attacks on individuals.

And finally, don't be afraid to try something different. Variety is the spice of life, as they say, and we don't need 10 identikit commentators