
Start at the core, so the basic skills:
- listening actively (also to what is not being said)
- being able to communicate what is in your head by speaking and writing
After that, you can build more specific skills on top:
- ABM
- Being able to ask right questions to get a grasp of the real issue / problem
- Being able to form a good organizational view
Extra Resources
Daniel Pink's master class. Even though it's not directly related to what we talk about here.