It is all very well saying your goal is to win a battle or a campaign; the question is how? You need a plan.

First things first before you press the start button read the briefing if it is a battle school mission it will at least have your ORBAT (probably) Who is your under your command, what resources have you got? Can you change the load out of your HQ squad? Is there some tasty weapon available you might need in your HQ squad? You may have some intel (often sketchy but it may contain little gems) Look at the map; where are you, where is the enemy? What is the mission?

Think up a plan!

Support is there any? Artillery can it be preplanned? Have you got close air support (CAS) Ammo trucks where can you place them, ditto fuel and repair?

Is there a field hospital? Arrange transport to and from it, for wounded crawling soldiers, other wise they slow you down. Place your ambulances at a forward protected spot. Ensure egress routes of groups and teams go there, put an ammo truck there for rearms.

In attack what is your ingress and egress route? You need both, any fool can get them self into trouble; the question is are you bright enough to have a preplanned route out of trouble to your rally point, a defensible piece of ground? 

Good rally points are forests, especially if you are trying to break contact with armor, they can not drive through thick forest and they find it a damn site harder to shoot you. Another good rally point is the reverse slope of a hill or ridge, the enemy cant see you and must skyline themselves to get at you. Towns provide cover and can also be good rally points

Got the Plan?

When you have the plan hit start and straight away hit slow time [CE 0 0 6]. Set up your plan. You can set units to hold at the start if you need to scout (see the squad tactics page for how to scout)

IS there an SOP?

SOP stands for Standard Operating Procedure; it is a ready made plan no need to think just do. Have a look at the US Army Field Manuals for some SOPs.

Infantry in defense dealing with armor

Always seek to canalize armor into killing zones. Choose the ground your going to let them into so that they present the juiciest targets. Make use of choke points like passes between steep mountains and gaps in forest. Get them to a point where their better weapons can not easily be brought to bare. Restrict their  vision by getting them to go into areas where there are obstructions to vision e.g. built up areas or forest groves. Restrict their movement by getting them into areas of obstacles either geographical or fixed defenses such as sandbags dragons teeth and AT mines. Booby trap their egress route. Hit them hard once in counter attack then decide if you need to move back to your rally point (Which if you are a good little officer you will have pre planned so you just start the troops in WP mode to enact; you are a good little officer aren't you?)

Spoiler alert for BS02 !

A simple example of this SOP can be applied to BS02. If armor is in the lead attacking a built up area let it partway into town place AT mines 30 to 50 meters or so into town. Place radio operated satchel charges 30 meters out of town in the direction the attack is coming from. Get your self and your infantry to the opposite edge of town to the attack. When the tanks are in town there vision is restricted when they start hitting the mines you counter attack with rockets. The tanks will seek to get out to clear ground where they can bring their weapons to bear. They will retreat; when they do explode the satchel charges there will probably only be some tidying up to do with the tanks. Now re-man any strong points, to take care of the infantry. Try this and you should be able to play BS02 with near zero casualties. Without this plan you may loose the whole platoon.

Battalion Artillery 
What are your preplanned fire missions?

Section AT
One on one with a MBT he don't stand a chance. You have to give him a plan.