He said: "The first two or three years of management, if it wasn't written in the brochure in front of me, I'd sulk or get a pet lip.
"Hot-headed would probably be the word to describe me when I was young but I have now learnt it is not always what is written in the brochure, so I go into it with my eyes wide open."
Bruce believes that after spells at Bramall Lane, Huddersfield, Crystal Palace, Birmingham and Wigan (twice), he is now at a club where he can finally achieve his ambitions.
And he reckons he joins Sunderland at the peak of his managerial powers, adding: "I'm 50 times better than I was when I started out.
"In my first year at Sheffield United, I had six chief executives and I found it very difficult but experiences like that stand you in good stead."