I finally figured out how to do it on non-ranked matches. However, when I make a ranked match and push triangle, nothing happens. So, how do I play my friends to also get ranking? Otherwise I feel like I'm just wasting time if I'm playing but have nothing to show for it.
You can't specify your opponent in a ranked game because that would allow people to 'cheat' the ranking system by simply having your friend allow you to win again and again.