Most advice boils down to the advisor recommending others to be more like himself. The advice in this blog post is basically for someone with a similar set of career goals and interests, and would allow the recipient to do modestly better than the author on his own career track.

I did this for a long time. I lift weights, so I recommended other people to lift weights. I read classic literary fiction (Tolstoy, Marquez) so I advised other people to do the same.

My best advice now is to deeply self-analyze your own psychology in terms of the Big 5 trait system and then pursue a career and lifestyle based on this assessment. Do not try to become a doctor if you are not conscientious. Do not go into sales if you're not extroverted. Travel is good for open-minded and extroverted people. If you're neurotic, develop lifestyle habits that will help address this condition (meditation, yoga, hiking).