It's my first post, so correct me if I'm doing it wrong 
After checking youtube and other sources for it, I really haven't found much. In case you're not aware of the duplication glitch out there right now, I'll explain it with steps.
- Go to your home in Skyrim, (or Solstheim, you filthy dunmer) with a follower of choice.
- Drop the items you want to have duplicated outside of your home. You MUST drop the items individually, one by one, or else it will not work. NOTE: Sometimes an item may not be duplicated, but I've only experienced it with it just being one item, so don't fret, it won't be deleted. Just not duplicated.
- Have your follower pick up all of the items, and then then tell them to wait outside of your house.
- Go inside of your house without your follower, and then go back outside. The items you dropped should still be on the ground, but also in your follower's inventory.
Now that I've explained that, I'd like to add on to it and how I've managed to improve it, and make it more efficient. One way is that if it doesn't work at your house, you can go to the Ratway, and go to the door of the Ragged Flagon. I always go here because it's guaranteed to work. Do the glitch the same way, but using the Ragged Flagon as your "home".
Another way I've found how to improve it is to, once you duplicate it once for a decent amount, but you need the item in bulk, tell your follower to pick it all up again so you don't have to tediously drop the item one by one. (Example, say you want 200 soul gems, duplicate 25 so you get 50. Have your follower pick up those 50, and then repeat for another 50, and so on.)
I can easily get both enchanting, smithing, and alchemy to 100 in under a couple hours just doing this. It's an extremely easy glitch once you do it and get used to it, and even more useful. I just wanted to share, since it's how I get stuff to 100 easily when I don't want to grind it all out. Have fun! 
(Feel free to share how else you can improve this exploit!)
It's my first post, so correct me if I'm doing it wrong
After checking youtube and other sources for it, I really haven't found much. In case you're not aware of the duplication glitch out there right now, I'll explain it with steps.
- Go to your home in Skyrim, (or Solstheim, you filthy dunmer) with a follower of choice.
- Drop the items you want to have duplicated outside of your home. You MUST drop the items individually, one by one, or else it will not work. NOTE: Sometimes an item may not be duplicated, but I've only experienced it with it just being one item, so don't fret, it won't be deleted. Just not duplicated.
- Have your follower pick up all of the items, and then then tell them to wait outside of your house.
- Go inside of your house without your follower, and then go back outside. The items you dropped should still be on the ground, but also in your follower's inventory.
Now that I've explained that, I'd like to add on to it and how I've managed to improve it, and make it more efficient. One way is that if it doesn't work at your house, you can go to the Ratway, and go to the door of the Ragged Flagon. I always go here because it's guaranteed to work. Do the glitch the same way, but using the Ragged Flagon as your "home".
Another way I've found how to improve it is to, once you duplicate it once for a decent amount, but you need the item in bulk, tell your follower to pick it all up again so you don't have to tediously drop the item one by one. (Example, say you want 200 soul gems, duplicate 25 so you get 50. Have your follower pick up those 50, and then repeat for another 50, and so on.)
I can easily get both enchanting, smithing, and alchemy to 100 in under a couple hours just doing this. It's an extremely easy glitch once you do it and get used to it, and even more useful. I just wanted to share, since it's how I get stuff to 100 easily when I don't want to grind it all out. Have fun!
(Feel free to share how else you can improve this exploit!)
I haven't heard of people using Dragonsreach for this glitch before either, so tell me if it ever bugs up, since I don't really like going to the ratway for duping. (Though the loading screens are shorter)