Create the following class:

Primary weapon: Any light machine gun (except AUG HBAR) with extended magazine attachment (optional).
Secondary weapon: A launcher (not the Thumper or RPG7x2) that can heavily damage a Pavelow.
Equipment: Tactical insertion.
Special grenade: Your choice.
Perk 1: Scavenger.
Perk 2: Cold blooded.
Perk 3:Your choice.
Death Streak: Your choice.

After you make this class, host a private match or a split-screen match. Make sure that your friend has a class with Hardline, and the Pavelow as one of their Killstreak rewards. Allow your friend to kill you enough times until they have their Pavelow. When their Pavelow is out, use your rocket launcher to hit it. If it is not destroyed the first time, use your Scavenger perk to get more rockets. Immediately after the Pavelow starts to spin out of control, take out your light machine gun and rapidly shoot at it. Each bullet that hits the spinning Pavelow will count a toward Cold Blooded Pro. By doing this, you can easily earn Cold Blooded Pro within a five minute match.