There's a lot of guides here, sure. But this thread is for the LITTLE things that you found out, maybe early on, maybe WAY later on. For example: Almost everyone knows the control+shift trick, to bring up everything clickable. Did you know you can right-click to get rid of the gumps in your way to see what's below? I didn't until yesterday Today I learned: when you're adding items to a BOD to complete it, you can just click on your pack instead of each individual item! You can use alt+right click to auto follow people! And I'm sure there's more. Share your little tips and tricks here!
Another one that made my lumberjacking easier is to use "all guard me" with my packy instead of "follow" - he actually stays close to me instead of wandering off
The bag at the Paperdoll is actually helpful! Organzie Agents - love them Hotkey to resync and one to stop a running macro Hotkey for screenshots (against client freezes when death screenshots enabled, use it after logging in)
Having a loot hotkey is very useful. Set the restock agent with all items you want to loot, like gold, reagents, gems, potions, arrows, etc. and then a hotkey to initiate it so you can target a monster's container on the corpse, or other containers in game. Makes hunting so much easier than having to squint and drag stuff a few pixels wide
On the Sell agent, you can set the hotbag as your actual backpack in your paperdoll as well. So if you go to a npc and do vendor sell, they'll buy straight from your backpack. Just make sure you aren't holding things you DON'T want to sell!