A very wide spread behaviour is to focus on details that are irrelevant to such a degree that it takes focus away from the actually important overarching idea.
The basics are always the most important thing to get right
I’ve written about the pareto principle before and even if it is not necessarily strictly true it is an extremely useful heuristic. I actually do very little in terms of advanced stuff or focus on others. I just buy and repost auctions three times a week. And it works!
In gold making there are really only two things that really matter. You need to post the items you want to sell on the auction house. And you need to make sure you obtain them cheaper than what you sell them for.
Everything else is just ways to improve these two activities by either setting smarter price points, obtaining your stuff more cheaply or posting at better times.
Start with the core…
The core of gold making is to post items that people want at reasonable prices. Get more items and post them. Don’t spend time analyzing data on the undermine journal or think too deeply about pricing a new item. Very basic operations in TSM work super well. Most of my operations have been unchanged since Legion.
When starting out your bread and butter will be crafting and low level flipping for a long while, so just get experience with them. Once you max out on professions you can start optimizing your settings, until then you are better off just adding professions.
Keep it simple.
Buy materials cheaply, craft useful items and sell them for 120% crafting or more.
This formula has NEVER not worked!
Once you’ve got one profession locked down then you add a second. Then you level another character to 120 and get a third and fourth profession.
You don’t need to know when materials are cheap, just run a scan every time you are on. Snag up whatever you know you can craft and sell in a week, then do it again.
Once you have this nailed down you can start adventuring into higher level flipping, resets and other shenanigans.
Stay away from the flashy stuff
The flashy stuff is generally not worth it until you already have a million gold. Resets are more for fun than for profit. BoEs and battle pets take a lot of capital to get started and cancel scans are only worth it if you have a ton of time.
Add new markets first, then optimize, then go crazy when you get rich!