There are 56 missions. You are allowed nearly 7 days (6 days left as of this post) to complete all the missions. At minimum, you should aim to gather 15000 points to unlock the A-Wing Strike (Rebel) or TIE Advanced Strike (Empire).
With around 5x the missions of Campaign I (The Dandoran Conflict), you need to be efficient. The guide give you an outline so yo can plan your course. Keep your production queued and building Heroes and units so that as soon as you finish the current mission, you will already have units ready for the next one. Defensive missions are a good opportunity to catch up on product and fill up your transports.
Anytime you run into a mission you cannot complete, focus on getting at least 1 star, and just move on to the next mission.
Here are the missions:
Level 1-8: Destroy half of the base for 1star, the HQ for 2 stars, and all the buildings for 3 stars.
- These are very easy and can be beaten by just one Hero
- You should have no problem
- These are nearly as easy. Nothing a Hero plus one or 2 units can't handle
- Use pathfinders or scout to speed up the resource collection once your Hero destroy the turrets
- Again, should be no problem
- These get a little more difficult
- Mission 24 was the first one I could not get 3 stars on my first try. I suggest you move on and come back later to get 3 stars.