For professions, most people pick 1 production skill (Blacksmithing, Leatherworking, Tailoring, Enchanting, Jewelcrafting, Alchemy, or Engineering) and 1 gathering skill that is associated with their production skill. This makes a lot of sense generally, but the interesting thing is that it is amazing how little benefit there is from any production skill versus the time, money, and effort required to advance it and even produce from it.
Production skills are not profitable. The end products almost always sell for less than the value of the materials required. Massive amounts of valuable materials are typically wasted just to advance skill level. Tons of money spent to aquire plans. Much time and effort...
Gathering skills are a boon. They take no special effort to advance and just the typical training fees.
Take two gathering skills... (be careful combining herbalism with mining...only one tracker can be used at a time.) Gather everything you see and sell it all in the AH cheaper than anyone else for the most part so that it sells easily. Watch your wallet explode with gold...
And, if you really do want something from a production skill...potions, sharpening stones, armor, enchants, etc... Just go ahead and buy what you would have otherwise produced (most people actually produce very little for themselves) and you'll still come out way ahead.
The problem is just that there are too many producers and not enough gatherers...server economies reflect that in pricing powerfully. So, there's a huge opportunity to "cash in" and be a gatherer.
