After reading the warning at the top of the forum that I have been a member for 201 days but haven't posted anything yet so I may get hunted down and smushed into pieces; I decided to start an interesting thread.
So let's say, you had to go back to when you were a complete noob, but it was current WoW version, and you had to pick the most valued tricks you've learned over the whole of your WoW career to take with you, what would they be?
I'll start with a couple of obvious ones;
Grinding is NEVER the best way to level, questing and using a guide is vastly more fun and faster.
Auctioneer and all related addons are HUGELY useful (and very easy to use) when making the most money from your drops, and making money from other people.