Most people will always tell you that gathering professions are the only way to make gold, and that most often crafting professions are going to lose you money because you’re going to be much too interested in gaining levels and will spend gold trying to make gear.
The thing these people don’t understand is that first of all, the gear you make does have an economic value. You can get back what you paid for in materials by selling the gear on the auction house. Also, you get to level your profession through the means of buying auction house materials and crafting more gear. The higher level the crafting profession, the more gold you can potentially earn through the use of it.
Once you can make some rare (blue) gear, this is where the money can really start flowing in. Of course making these equips is going to cost much more, but so does buying it off the auction house. If you’re the only one selling the equipment, you can easily make tons of gold through this way. Sometimes, grinding for the materials when they’re not on the auction house is the best way to make the gold. Grind on stuff that you can skin for the gear, or run a search on thottbot.com for the mob that drops the particular item you need. Of course this can take some time, but the gold outcome is often well worth it once you find one that works well.
I’ve noticed that one of the easiest and most reliable ways to make smaller scale amounts of gold is to change materials. For instance, buy stacks of light leather and convert them to medium leather and resell. Buy medium or light hide, cure, and resell for more than you paid for the salt. Also, another good way to make money through this is to buy ruined leather scraps, turn into light leather, and resell. Of course you need money to make money through this method, but you can still make a decent profit in the long run.
Taking Advantage of Trade Channel
The trade channel is a great way to make the gold flow in as well, because people that might not even check the auction house for the gear you can create might be tempted to view what you can craft them. Now, with the convenient feature of being able to link your profession to anyone, people can easily see every item that you can possibly craft for them, as well as the materials they will need to provide you with in order to create it. They will also know a rough estimate of what they should owe you after the whole transaction is complete if they used your own materials.
There are a few other ways to make money with leatherworking, and with crafting professions in general, but I would say these strategies are some of the best ways to make gold through the use of crafting, and leatherworking in specific.