Use the overlays as much as you can. The range, movement,
and visible hexes overlays are invaluable in determining
the right course of action and avoiding unfortunate accidents.
Units can easily get lost in trees and other parts of the
terrain because the map palette isn't very broad. To help
sort out matters, turn on the unit bases. The game may look
less realistic, but turning on the unit bases helps you keep
track of all those little infantry platoons.
If you are partial to flanking movements, be sure to turn on
the vehicle facing option, so you get the maximum benefit
from your maneuvers.