Here goes:
1. Read manual. Perhaps twice because there is so much

2. Go through tutorial. It is nicely done and it will provide great help to you
3. Start with smaller scenarios. I like Shiloh for that. 11 turns if I remember well and with armies and all...
4. After you coverd those three steps go to the big league: campaigns. Perhaps first with the Union.
Anyway you can start with campaigns right away, as I did, but you'll pretty sure get lost

One step at the time and you'll be fine.
I play it since I became beta and I still didn't get tired of it. I even love it more with every new version and update. Heck, game is getting better and better every day

Plus, not sure if I can say this


Godspeed