I got a couple things I do with my thief but I'm completely unconventional. First things first is your template.
I use:
Hiding: 100
Stealth: 80 (enough to never break with no armor)
Detect hidden: 100
Stealing 100
Snooping 100
Rest is optional. I took
Tracking: 100
Magery: 50
First and foremost, you absolutely need an ethereal mount for this build. Your weapon is your stealth. I like to profit off the invasions in town. Avoiding the champ at all cost, I'll walk around stealthed and loot as much gold and magic items I can off monsters because people will be too focused on surviving the invasion, but not me because I'm always hidden. I like to have a packhorse, alt, or a near by or a hidden box that I can stash all the gold in. The next thing you need to look for is dead people. Stealth up to their body, mount your horse, click the body to open it, rehide, and then pick what you can take the fastest. I like to take bags of regs or any high end weapons I see. The second you take anything the game begins because you'll be a grey in the middle of a bunch of blues but they'll all be busy. So at this point you need to focus on your escape. If you pull off a hide anywhere, dismount and stealth to safety. This is by far the best way to be profitable however there isn't always an invasion going on. Doing this for brit invasion yesterday I managed to look 2k of each reg, 25k, and a bunch of magic weapons. The weaker magic weapons sell good at vendors.
My absolute favorite part of the invasions is when its over because this is where I'm most likely to get vanq weapons and this is the same strat I use to pick off random people at banks. The most important part of this is target acquisition. First, find someone that has a weapon you want. The lighter then better because you'll be less likely to be guard whacked. Bows are very popular and easy to take. Once you find a weapon you'll want to snoop their bags and look for a spellbook/ruin book and see if they have enough magery to recall. If they do then you have a perfect target. At this point I'll put that person on tracking so I can hunt them. If they run off, you want to be able to find them. A lot of these guys will hide. Even though you'll be GM detect hidden you don't want to use it. Don't alert them of your presence because your stealth is still your weapon here.
Now time for some macro control (you can do this without razor). You want to set the weapon as your last target. I usually use my newbie dagger. You want to make sure you're close because you're going to wait for them to recall. When they recall, the weapon goes into their pack and you'll have about 2 second window to act. The second you read "Kal Ort Por" you execute your steal last target macro. They will be stuck in their recall macro and be completely defenseless and most likely will never realize what happened.
Also, just for fun and practice, I like to target reds. These are people that will absolutely kill you if they find you and they are my favorite people to mess with. Using stealth I'll sneak up next to them (even if they are in a group) and pop a few explosion packs. They'll freak out and try to reveal you. This is a game to you but to them if they don't find you they can lose a fight so they'll spend a lot of time trying to hunt you down. using stealth you should be able to get in and out before that happens and if you die, who cares, you're a thief. I like to also put them on tracking so they can't ever evade me, and if they try and hide I'll pop them with my detect hidden. If you can manage to steal regs or bandaids from them and get away they'll get paranoid because you control the situation. The other way to use reds is dungeon hop as a thief. I like destard because the mobs are a big deal in there. Follow the reds and loot bodies they leave behind. Use your detect hidden to get reds and blues killed alike because the more dead bodies there are, the more you profit and don't forget that a hidden pouch behind a wall is a lot harder to find than a packhorse for your remote hording options.
Stay profitable my friend.