Note that in order to get this, you must be connected, not just to Xbox Live, but also to EA servers. EA has a habit of disabling servers and discontinuing achievements, so get this achievement early.
Once you're connected to EA, start the tutorial mission. It's the second option under "Tutorial." There will be three waves and an evacuation:
Wave 1: No enemies. Destroy some stationary objects as marked.
Wave 2: Walk into a capture point. Defend it and kill about three enemies. Make sure you take cover.
Wave 3: Revive an ally. Walk over to him and hold
Evacuation: Return to your starting area. Stay alive until the timer reaches zero. Watch out for the explosive barrels nearby.
Achievement should unlock when you see the rewards screen.