1. Go to the Segmentation section in the sidebar navigation.
2. Then Choose List on the drop down options.
3. Select any form the lists but it only applies for Dynamic Lists, You'll see a gray "dynamic" to denote a dynamic list.
4. Click the More dropdown button in the right hand corner, and click Duplicate List.
5. You will be routed to a page where you can make changes to the duplicated list. Once you're done editing, on the upper right part of the page click on Save and Exit.