Some of these will seem obvious. Others might not. Let us just leave it at that.
And anyone can feel free to add to this as they see fit.
~ Some houses have multiple doors. If one door has a more difficult lock, it probably gives you easier access to the valuables in the house.
~ NPCs zone with you if close enough and you zone while they're talking to you. You can remove them from their own buildings in order to better burgle this way.
~ Attempting to pick a lock isn't a crime if you cancel out of it.
~ Since time stops while you're in lock-pick / inventory menus, you only need a brief moment of being unseen to access them... That "Shadow" perk from the Sneak tree can provide just that, if timed perfectly.
~ The old bucket-on-the-head trick? Well, it works, but only if they stay totally still and you're really good at getting the bucket on their head. I wouldn't rely on it, personally.
~ A better option for stealing loose items in shops is to knock them to somewhere the shopkeeper cannot see... using another item as a hockey-stick if necessary. An awkward process, but occasionally useful.
~ For upgrading the Thieves Guild, the Burglary / Numbers jobs are easiest... which is convenient as they're the first on their respective lists.
~ If you're caught stealing or in any other crime, while it might seem clever to drop all your stolen gear before the guard gets to you, it might just be easier to serve time in jail and then steal it all back from the evidence chest... Depends how fussy you are about your skill progress.
~ Normarily, the highest pickpocketing chance you can have is 90%, and many things will be 0%. However, if you have a Paralysis poison and the "Poisoned" perk, then by planting the Paralysis poison on your mark, you can clear out everything in their inventory with 100% success while they're getting up (it will still show normal success rates, but everything will succeed). You won't get any pickpocket training for this, but it is perfect for stealing huge amounts of cash (e.g. if you've just paid a Master skill trainer to go up 5 ranks) or very expensive items (especially with the "Misdirection" and "Perfect Touch" skills).
I'm all out of helpful tips for now... but I'm sure I'll discover more later.


yes, but sometime's it's just easier to go to bed... G'nite.