First thing's first, you need to control the Spartan Laser, found on the ridge in the middle of the map. Zoom in and lead your target as it charges up then let rip. It'll take out any vehicle and whoever's in it. Due to the size of the map it's perfect for sniping people from the back of your base or the little tunnels that line the sides.
Another important weapon is the missile pod, located in the back of your base. This heavy weapon homes in like the rocket launcher did in Halo 2 but you'll be a sitting duck while carrying it around. Try jumping into a Man-Cannon and attacking from the air. Push the exploding barrels into it too, just for a laugh.
You'll get the Trip Mine on this level, which will take out anything that hits its sensors. Keep this in your pocket and drop it just before someone runs you over in a vehicle. BOOM!
Keep an eye out for snipers in the main camping areas: on top of the two bases; hiding behind the crashed Pelican; in the secluded caves on the extreme left and right sides of the map and,oddly enough, on the hill in the center of the map.