Hi
There have been threads on this but they have probably been archived by now. I would just start and if you get stuck ask a specific question and someone will nelp you out.
As to pointers, read the description very carefully and do the tasks that are specified to win the game. In most battles you are outnumbered so do not expect to stand up and fight a straight battle - you will lose. Instead use some light forces to draw off a part of the enemy army while you destroy the rest or complete those tasks. Good luck.