It's very simple.

We use ACE so you have to have Laser Designator batteries in your inventory as well.

Simply point your designator at your target/building, etc. and press the fire button. You'll see the laser icon activate in the top of the designator. Hold it there. As long as your Air Support is in the air, they'll see the target and proceed to drop a whole heap of badazzery on said target. As long as you have the laser active, the ALiVE CAS will continue to bomb that target until it runs out of ammo. Once you're done, just press fire again to turn the laser off.

We have been using the A-10 to assist in destroying Taliban installations on our server in our current mission. Lots of fun! It also works with Human pilots as well of course. Works with Helos, Planes, etc.