Before you blindly go into champion select with your duo partner... Stop, in the name of elo! And think about what type of duo composition would best work for you and your partner. Can your friend jungle especially well? Perhaps you should play mid lane to give your team some map control. Or if you can rock a solid Vayne, your partner could grab an aggressive or non-traditional support. Whatever the scenario, be sure you figure out how to optimize your games together. Because solo queue is a strange place, and you never know what mongoloid might end up on your team.