There is a difference between "playing a character smarter than you" and "playing a character smarter than you can imagine." Obviously in either case it's easier the more intelligent you are. Zarrgon is focusing more on the latter case, whereas I understood the main point of the OP to be the former, and Zarrgon seems also to be focusing on the difficulties--more prevalent when playing a being more intelligent than you can imagine--more than on offering advice. Most of how it's going to work--if it's going to work--is likely to involve some amount of metagame thinking, some amount of prep, and some amount of help from the GM and the other players.