I have had lots of mentors and I've never asked.

The value a mentor gets is a good feeling that they are creating impact by spending time with you.

You give them this feeling by actually DOING the stuff they advise you to do or help you to see.

It's not often that someone actually takes advice and runs with it and comes back to say "Thanks, I did it. It gave me this result. Now I have another question..."

Forget strategy. Simple principles are all you need.