Going dual-gathering helps out a lot. Crafting for money doesn't work out. If you craft at a normal pace (when you have the mats as opposed to intentionally going out and farming mats), your recipes will never catch up to your level. You'll be crafting stuff for several levels below you. If you want to make your own stuff, odds are you'll either have to farm like mad or hit the AH for mats... which is kinda redundant if the point behind all this is to make money.

I was dual gathering for 1-50ish (herbalism/skinning) and avoided buying stuff from the AH till I dinged 60. Never really ran into cash problems. And once you're 60 you can powerlevel your crafting skill (alchemy in my case) in a day or two with enough cash.

Just avoid the AH until your main is 60. It's fine for twinking your alts, but no point spending cash there if it's your first char. The items you get will only be useful for a few levels, and you'll be spending a tonne of time trying to scrap up cash for your mount/training.