This is not difficult at all. To make it easy on yourself, host a game of Team Deathmatch on Canyon with the kill limit set to 5. A win should take no more than a minute (assuming you're the one winning). This must be done in a Ranked Match.
You can also boost this using the same method (which you may NEED to do, due to dwindling number of players) by having at least 3 of your buddies join your match and taking turns killing each other. Have the team getting killed run to the bridge in the center of the map and pick them off quickly. You can finish a game in under 30 seconds.
(Edit) To clarify: You do NOT need to have the most points, you just need to be on the winning team. You can check your progress by viewing the achievements menu from the main menu.