ok-ok I'll tell you all how I've done that with my mates.
1). You need 11 friends.
2). You need a friend who has a good connection TO BECOME A HOST and at the same time A HOST who no one joins to. You know what I mean? e.g. say you have 6 friends in a party, then you join a match and you lot just wait for decades in a lobby and no one joins. That's good, because if no one joins it means you can invite the rest of your friends and fill the lobby up.
3). The game mode is NORMAL search and destroy.
4). YOU need the following perks and items: ONE MAN ARMY PRO (if you don't have it because it unlocks in lv.45 I think then don't worry, instead of this have a tactical insertion in your equipment and let your friend kill you - will explain later). RIOT SHIELD. TACTICAL INSERTION - this is to respawn faster, bla-bla-bla. WEAPON - RPD (that's what i used).
5). THE METHO

ok so you need to let your mate know what to do on the other side, because you can't hear your enemy. You need to get your Riot shield & RPD and tactical insertion with 1 man army perk. stand near your mate, let him have the riot shield on, tell him to crouch, shoot with your RPD, he will start getting +500 and +1000, then when your mate starts getting little points after a while, he should STAND UP from CROUCHING, so you know (because there's no mic) that he's getting little points, now your mate should choose 1 man army and change to his RPD and do exactly th same to you.
I've done that yesterday for 2 hours again and I'm on 7th prestige (i don't add anyone, because I have maximum amount of friends).
HERE IS A VIDEO EXAMPLE: [ame="
https://www.youtube.com/watch?v=PEP4H-x3keg&feature=related"]YouTube- Cod:Mw2 Boosting 50k-100k Xp Per Snd Game ![/ame]
NOW YOU CAN THANK ME FOR WASTING MY TIME.... JOKING LOL.