You can choose to start making gold at any time, but let’s say for the sake of argument you’d like to begin generating income right away. Now, you can roll a Death Knight on a new server and end up with about 30g or so by the time you enter Orgrimmar or Stormwind. That’s without trying to make any money while you get out of the start zone. However, not everyone wants to roll a Death Knight and the start zone is lengthy (by comparison). So what about when you’re starting low level?
I recently rolled a Goblin on a brand new server, knowing nothing about the economy there. By the time I came out of the start zone (lengthy in it its own right, as is the Worgen zone) my Rogue was level 11 with just over 2g. That’s from vendoring almost everything I came across and ensuring I grabbed the items that had the most vendor value on my quest hand-ins. I also had a stack and a half of linen and a couple of Malachite. 
While not worth much, Plans: Copper Chain Vest also dropped for me in the Lost Isles. Armed with just those things, off to the Auction House I went and the first thing I did was hit search. Sorting by price, I could see the cheapest items listed. Before you buy anything, be sure to search out the same item with your Auction addon to see what the going rate is. For instance, I found Malachite for 99c, which is low compared to my regular servers. However a quick search found that to be the actual rate.
The next thing I did was list what little I could. A single stack of Linen Cloth went up for 2.5g. The blacksmith plans I tossed up for just 15s as the auction house had plenty. I could’ve held on to them, but I didn’t expect it to vary much. The Malachite I hung on to and I put in some low bids on Copper Bar. I would recommend bar or ore, whichever is cheaper. The eventual plan is to get a Mechanical Squirrel Box (or several, depending on finances) built. Even though I wrote about the benefits of the Squirrel quite some time ago, it’s still a great source of money.
I’m keeping things relatively basic, but there’s two things you can do next. The first would be get a profession and put it to use. If you’re not going anywhere, I recommend Enchanting. You can pull tonnes of low level greens off the Auction House and disenchant them into Strange Dust. It often has a reasonable value by comparison. The second option is seek out what rare spawn recipes are in your city and grab them, putting them on the Auction House. The Pattern: White Wedding Dress always sells decent and quickly, for example.
Cap that off with starting to run auction house scans right away, and you’ll begin getting an understanding of your economy (and start spotting deals). This will vary based on faction, server type, and population. When starting out, I prefer the low risk/reasonable reward method. You don’t have much capital to start with and the wrong investment could leave you with little to work with or completely tap you and result in having to quest or grind for startup once more. As you begin to generate gold, keep in mind previous methods I’ve mentioned for making gold. On a new server, the best one I can remind you of is Making Others Work For You. While that post suggested end-game items, there’s nothing to stop you from using the exact same strategy with lower level items as you can afford them or as you gather the materials. Really, it always comes down to strategy. The more you read and develop them, it comes down to learning which ones work best and applying them.
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