Smurf your armory page
When you start to get to the higher levels of arena play, enemy teams will most assuredly be looking on your armory page to see where your team's weak spots are. In Season 6, we played with a holy paladin who entered 5v5 matches with ~400 resilience. He was very squishy.
We told him to log out with a full set of PvP gear on that was gemmed and enchanted for survivability (resilience gems and stamina enchants, etc., the works). When enemy teams scouted his armory, they saw our paladin as a terrible target. In reality, he was the best target for them to attack, but we deceived our opponents with a "smurfed" armory page.
Armory smurfing is a 100 percent completely legal way of hiding information to enemy arena opponents. I encourage you to do so if you think any opponents will be attempting to view your team's page as a way of gaining valuable information.
Dummies aren't just for PvE
Practice dummies in Orgrimmar or Ironforge are great for figuring out optimal gear or maximum DPS rotations. However, high-rated teams very rarely practice on dummies. This is a shame, because practice dummies are fantastic for getting your switches down.
Compositions that rely on quick burst kills, such as 2346 (elemental shaman, destruction warlock, hunter or warrior, priest/paladin healer), would do very well to practice their switches on dummies. Before I hit rank 1 with a burst comp 5v5, our elemental shaman had the amazing idea of practicing switches on dummies.
Our elemental shaman/destruction warlock/mortal strike warrior trio went from killing enemies in three globals down to killing enemies in two globals. Once we started throwing in priest damage, we could take enemies from 100 percent to 0 percent (i.e., killing someone before his screen even shows him to be taking damage) very reliably. What's more nuts is that we were able to do this every 10 seconds because we were only limited by the cooldown of Chaos Bolt (which we had our warlock glyph for).
The practice dummies helped us practice. Who would have thought?
An important part of being successful in arena is understanding how your team functions versus how enemy teams function. If all the top teams on your battlegroup are spell cleave teams, you might want to consider making a composition to counter these spell cleaves.
Some people consider countercomping to be "cheap," "lame" or "cheating." It's none of those. It's awesome. Think about it -- if you can give yourself an advantage against the top 10 teams on your battlegroup just by playing a certain class composition, why wouldn't you? Why aren't the top teams taking advantage of this fact?
Countercomping is a part of arena. It's completely necessary, too. If countercomping didn't exist, everyone would just find the best 3v3 or 5v5 class composition and play it mercilessly without fear because there is no counter to it. This would be terrible, as only three or five classes would be viable within an arena bracket. If you don't have a geared PvP alt of that class, you might be doomed to disadvantage for an entire season. That sucks.
Countercomping is good for the game. Take advantage of it, and laugh at anyone who calls you names because you want to be successful.
Sniping and spying
Sniping and spying are incredibly controversial issues within the arena community, but I don't know why. Once again, this is one of these 100 percent legal things that some people consider to be cheating or lame.
A sniping team is usually very high on the arena ladders. My teams usually begin sniping when we're in the top 5, although we've done top 10 in the past. Sniping teams take maximum advantage of the in-game friends list. Social panel for the win.
Snipers create level 1 alts (usually on separate accounts, but this isn't necessary) on other servers to spy on rival teams. The spy will have everyone on the rival team on their friend list. When these rival teams queue up for an arena together, they all show up in an arena together, giving the spy valuable information -- the targeted enemies are currently playing an arena game.
The spy will quickly contact all of his arena partners to tell them that they should get ready to queue up for an arena match. The goal is to log on quickly, form an arena raid, and queue up for arena within a matter of seconds. When the enemy team leaves the arena, hopefully they will queue up and hit the sniper team.
The sniper team will have prepared by talking to each other on Ventrilo or Skype about the different strategies they can employ against the enemy team. They will have an advantage when going into the arena match by having foreknowledge about who their enemies are (remember, the spy can just check which arena they entered if it's on a different account).
Want to ascend the arena ladders faster than a fireman playing
Donkey Kong? Read Blood Sport for pointers on arena play. Don't miss our interviews with successful arena PvPers, and see The Art of War(craft) for the inside line on battlegrounds and world PvP.