Well if u r on the rebellions side take a small snowspeeder squaderon along with1 platoon of soliders and have bombers
the soliders are to protect ur command post. and maybe even make turrets
fly the snowspeeders to the enemies bases and destroy them one by one until the bombers are ready then then bomb their bases and retreat.
you may ask why attack and retreat? well that attack destroyed their bases and now all u have to do is bring a much greater fleet into battle on that same planet and you should achive VICTORY

If on the Empire
then take a small fleet of soliders, tanks (idk the proper name)
use the tanks to attack any enemy forces that get in your way but make ur attack last a few seconds then keep moving to the enemies bases and boost your firepower and destroy their bases until the bombers are ready. then bomb the planet and Retreat or autoresolve then attack again

IF THIS DOESN'T WORK THEN BUILD UP YOUR ARMY AND ATTACK THE ENEMY FULL FORCE