The BEST practice is to play tons and tons of games against teams that beat you. Seriously. If you want my advice. Don't play 10 games, play 50 a week minimal! Until WotLK. Get more experience. Don't let losing put you off, you'll profit from the losses sooner or later.

I played 80 games a week on Vindication(EU) I lost a ton of games, was at 50% win rating. Thing there was, there usually weren't more then 2 teams playing at the same time in 5v5, so often same team over and over if they don't queue dodge. It was hard for me to climb. But now I migrated to a more active battlegroup. Started with 22 wins and 6 losses on the counter, then I faced a team that could beat me a few times, now at 23 wins and 11 losses. But basicly, doing quite a bit better then on my old battlegroup. Still, I could have queue dodged when I lost. But in all honesty, the last fight I did vs them compared to the first, I did improve, and that is what it is all about in the end.

You won't be able to reach 2k rating by queue dodging. Sooner or later you'll have to adapt to the teams you face and start beating them. So why not get the experience while gearing up first.