Advice Monkey
A (usually quite arrogant, hypocritical and narcissistic) person who feels compelled to give other people tons of personal advice and perhaps even detailed instructions on how to live their lives. This person is always never in any sort of position to actually give advice, being almost defined by their poor choices and often barely functional or even dysfunctional in their own lives.
My friend Michael the Advice Monkey won't shut the fuck up with his advice on health and street smarts; he's also on several antidepressants and lives in a Section 8 apartment with his cat.