The main tool for any serious gold maker is TradeSkillMaster. It is an addon suite with a desktop application that downloads price data and allows you to create rules for easy crafting, mailing, shopping and posting your items on the auction house. It has a premium service that includes e-mail notifications for great deals and importing great deals as a shopping scan.
Similarly, when earning by volume, do not overload the AH with your items. Basic supply and demand: too much supply will make your wares too common and unwanted. Furthermore, with great demand and a cheaper price, you may end up starting a price war with your competitors, with them actively trying to undercut and outdo you. Moderate the amount of items you're selling on the AH to small batches, refilling them only when sold out.
If you've been away from WoW for some time, you may not know that the game's Legion expansion focused on powering up an impressive "Artifact Weapon" throughout the duration of the expansion. In short, players have been using the same weapon for about two years now. Artifact weapons were pretty cool and bosses did drop Relics which were used to upgrade them. But after two years of using the same weapon, many players are looking forward to the thrill of having an actual weapon drop off of a raid boss again.
The Auction House is always the best option for getting good equipment at a good price. The only items you should be buying from Vendors are basic consumables: food, drinks, arrows, bullets, vials, dyes, etc. Most other things should come from the Auction House, as they are generally cheaper. Keep these tips in mind when buying items off the Auction House:
In addition, you'll want to pick up leg and shoulder enchants and have them in your bags. These enchants have a level requirement of 80/85, but can't be placed on items above iLVL 136. You can get around this by having a level 85-100 character apply the enchant before mailing it to the character you're leveling, thus getting use of the enchants before level 85. I've personally confirmed that this works.
If you want to spend as little time on your alt as possible - just do Legion Invasions. You can use sites like (https://wow.gameinfo.io/invasions) to track when the next invasion will be. Log in, fly to the closest world quest, and once there - right-click on the quest's name in your quest log and "Find Group". Sign up for some group, or if there's none - just start your own immediately, and people will come to you. It is 10 times faster to do invasion quests in a group. Once that particular quest is complete - leave the group, and fly to the next one, where you should find another group. Don't expect the group from one world quest to follow you to the next. Then you simply log out until next invasion. You can do 1-2 invasions a day, and each invasion will give you about a level or 1.5 of experience, if you have full heirloom gear. Each invasion will take about 20 minutes.
To do this, you will need up the WoW Legion Expansion, a maximum of 10 characters including a Herbalist at Lvl 100+, and, of course, Seeds! You can get the seeds by farming them, doing Herbalism World Quests, or buying or trading them in the Auction House. Usual seed raids can are for 30, 50, and 100 seeds and raiding them can take up to a maximum of two hours.
This is an infinte farming spot that takes place just east of maraudon. It requires you to stand in a specific spot which will allow you to kill all the slitherblade naga that surround the river. This spot is generally a GREAT spot since the mobs respawn instantly after death. You will get an obscene amount of silk, wool, greens, and low level patterns. It's one of the only remaining infinite respawn farms left in the game.
Now that we have a lot to post we reached a point where we have to plan what items we post on an 12-24-48 hour cycle. The auction house fees for Warlords of Draenor items are extremely high. And the values of the items are really screwed up. A lot of the weapons or armor has an item value of 5-10.000 Gold. But they look plain bad and the chances of selling them is pretty low.