Do's: I love a guy in a well-fitting slim suit. It tells me that he has invested in himself and wants to stand out from the pack. There is at least one occasion in every man's life where a suit is required, but to me, suits are best worn often, when least expected, and in a way that expresses his personality. Wear it with an unstable cotton Rick Owens tee, a flower in the lapel, a subtly odd tie, sleep in it, trash it, ride your bike in it but mostly love your suit and people will take notice. For Blackbird, I created The Right Suit to give guys that perfect high quality suit, straight off the rack for 40% less than other brands.
Don'ts: I hate being negative ;) Don't be afraid to be yourself. Don't worry about what anyone else thinks of you. Experiment and find your style.