> I’ve never done this before
Really happy you mentioned this because on the face of it, this is a colossal waste of time.
Shadowing someone in the duration you have mentioned is the equivalent to buying a Tony Robbins book about Entrepreneurship, reading it and then proclaiming to be an Entrepreneur when really Mark Cuban has it right and they are just a Wantrepreneur.
I know this sounds pretty harsh, but you have no skin in the game. You won't be making any decisions, you won't feel the weight of them either. You won't be telling staff to start and project and then see all the problems associated with getting it finished.
There's no muscle memory to be gained here.
Here's what I would do. Tell your friend, instead of shadowing to make you a manager with a member of staff. To then give you a small project to deliver. Something that's well outside of your comfort zone. Ask him, to have himself or another manager to be available for mentorship when you need it.
Now you'll be in a position to find out for yourself:-
1) What makes a good leader
2) How to effectively communicate to staff.
3) How to handle problems that come up in running projects.
4) How to plan a project and then to complete one.
5) How to manage a budget.
6) Everything else in between.
Doing is far better than watching and by doing so, gets you a lot of experience for when you want to do it yourself.
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Honestly though. I would just start my business today and have the CEO friend as a mentor.
Fail and fail often: https://www.youtube.com/watch?v=mNDA-o9yJNw