Another way, and the way i did it was this:
1) Skirmish, deathmatch, 1v1, Easy AI.
2) Be a Human leader, who you Vs is up to you, i just left both Alpha and Bravo teams on the default each time.
3) As soon as the match starts build/queue 14 warthogs, take your first warthog that is already built for you, send it right to the enemy base and attack it. These warthogs have the gauss cannon and a grenadier in the passenger seat. So double the fire power.
4) When you hear the voice over say something about a warthog being built/ready, press the bumper to select all units, and make them attack the base. Keep your ear out for the voice over and you'll have several warthogs attacking the base in no time.
5) This part is up to you. Usually it seems one base close to the enemy base is empty, if you want, take one of the warthogs attacking the enemy base to go search for a close empty one, build on it, then queue up more warthogs, and take the explorer back to the attack. (Then repeat step 4 over and over again).
This takes 2-3 minutes per map, keep an eye on your hogs to see if they are being attacked as sometimes Arbiter sends some guys out to kill you. Most of the time the match will end in a win right after the base is destroyed, sometimes however an enemy slips out the back, if this is the case take a quick look around the immediate area and kill whoever you find.