How to learn the finer points of trade for a noob?

I am very interested in learning how to efficiently trade and earn some currency doing so, but certainly a steep learning curve starting out. I know the basic functionality of the trad site, and have bought some tabs to make public that I set prices on items that I loot to try to make some exalts, but have had limited success on that front. A few questions:

1: how do you determine what an item is that someone might buy on trade? I generally have looked for rares w good mods, but I am learning often it seems people want “bases” more, but I don’t know how to differentiate something someone would want from just junk. Any advice?

2. I am trying to watch videos to learn the trade system, there are a million on YouTube, but it’s hard to know what’s good advice and not. If anyone knows any content creators that do well w the trade system and explain it clearly, would love recommendations.

Thank you!