Using BC client/version only guides to 58

[entropytouch]

In fact, the best thing to do if you boosted a character (or already had a 58) is to load/start from Burning Steppes and progress through EPL. Kinda sucks. The only guides for Silithus don't work because you can't start one of the main quests until 60.
This I get, since once the release happens you'll be able to start Outland at 58, but for now it kinda sucks...

[ZG Support 1]

We suggest for you to just run dungeons to try to get better gear to start Outlands with. Our Outlands guides will start at level 58, so you technically don't even need to worry about hitting level 60 yet. But if you just want to, and don't want to run dungeons, you could load up any guide around 54+ and just follow those, skipping anything you can't do.