Kaka, the game is not one tactic. You must to change the tactic depending what tactic use your adversary.
In the game you can give Red and Blue arrows on players. But this is not always good.
For example, blue arrows give only if the match is live. (if you want to keep your scor, you play defense).
Now, with the Red arrows is somewhat complicated... Why never you know if the red is right or not. But the right is to give on MR-MC-ML.
What i mean? If you play with tactic 4-3-3 you will give red arrows on MC*-mc-MC* (with * is red arrows).
But if you play 4-4-2 or 3-4-3, with red arrows only on ML-MR. and maybe on 2 ST. (Sometimes not always).

Here on forum have tutorials.
I hope to helped somewhat. Have a good game dude.