To give advice you must have knowledge, experience and practice. But that is the technical part. Then comes your personality and style, which in my case I am not willing to change even in paid advice mode.
But the most critical dimension is the type of advice. If advice is related to human matters like job hunting /search as opposed to Finance, Marketing, Management, then the issue becomes quite complex as personality traits, temperament, career, vision and Karma comes into play
I have been working in job search consulting for the past 5 years and it is not a piece of Cake. Sometimes changing people's frame of mind or expectations just becomes impossible. Some people just want to listen 👂 to what they want to here,not what others see.