Play all the tutorials first and get good at easy skirmishes before playing the Campaigns

Make sure you have enough power, the LC can be a pain to maintain power

If you are in serious war make sure to put your fighting unit factory on continuous of the unit you like

Try to find what combination works the best with what you like to do

Don't get too comfy with just ground or air units, get a good mix of them both

Your buildings should have Weapons/Shields on them 

Put your power in the back and make multiple ones for a general area

For the LC try to put main bases around the area for easy deployment

Use tunnels, they help greatly, you can stash a mess of units below and have them surface in a Crisis

Make sure to upgrade everything, and do frequent research, while building an Army

Remember Air units if you keep them moving can kill small annoying tanks/mechs

If you put your air support on mountains above you can baffle the computer while they move back and forth trying to kill it

Get familiar with all the units of all three factions

When stealing buildings, steal a power plant first, your power won't work on it.

HAVE FUN!!!!!!!