First look and see if it has bleeder valves somewhere on the highest part of the cooling system. If so use these to bleed the system. If not, then jack up the front of the vehicle or park it on a steep incline and remove the radiator cap. Make sure the radiator is full. Start the engine with heater set to hot, and watch for air bubbles escaping from the radiator. Keep adding coolant when the radiator gets low. When you see not more bubbles, you are done. Repeat this procedure at least one more time in a couple of days.