Stay close by and work together-Never seperate unless neccesary.
Once you have made contact, Fire Superiority is the key, as well is Speed in these small games.
Keep firing and keep there heads down and advance while they're ducking from your incoming fire. While your partner is giving suppressing fire advance quickly and swiftly so you'll be there before they even know what hit em. The faster you go, the less time they'll have to react and counter-attack.
Just remember-while speed is important, you don't want to go so fast that you get clumsy and take unnecesary risks. That and ALWAYS be aware-in these backyard games a common tactic for less experienced players is for one player to distract while the other "sneaks around".
While any plan can be mediocre, if caught off-guard it could end you. Quickly