Personally i prefer Villa map because it's small and great for close quarters.
Pick a gun you like and are GOOD with.
and choose Team Leader game. As it doesn't take long to finnish this game type.
and if you're not the leader, you can keep respawning
Avoid games like; Attack & Defend as they're not very long games.
Also, even though the Shield seems like a good option to use to stay alive, i don't recommend it as experienced players can manouver round you.