I know everyone has their opinion of how they got this, so I'll give my 2 cents too.
I'm NOT good at this game. Period. Like, seriously. For the longest time, I got my ass kicked from left to right, front to back. I was either last or second to last like every match. But then I got my crap together, and here are my tips;
I have been MVP with both the Leader and Soldier class on more than one occasion, and I've been 2nd and 3rd with both Scout and Scientist. The secret is to do objective based multiplayer. I highly recommend Conquest, like everyone else says.
From their, just stick to the objectives. Capture and defend the points. You get 3 points per capture, 2 for a defend, and only 1 point for killing someone. This easily allows someone just capturing to be the MVP, as it gives the most points. Using both the Leader and Soldier gives you more life and stronger weapons, which means longer lifespan and a better means of killing.
When you hear that a point has been captured or is being captured, race straight to it and do what you can. The more you try, the better the chance you have to get points. One match I got 46 points doing this, while the 2nd place guy got 31. I only got like 10 kills, but my capture and defend points alone put me in 1st place.
Just remember to pay attention to the objectives and go to the points quickly. If you're team is already in the means of capturing, hurry even more, as you will still net the 3 points for only being there at the end.
Hope this helps!