Personally, towards the end of the game, I just attack. But it may have something to do with max stats on two of the three peeps in the party (Quistis & Rinoa have max HP, Str, Vit, Mag, Spr with junctions & stat-boosting). *shrug*

But at the beginning of the game, I play a lot of cards to get good magic early on, like getting 100 Flares before leaving Balamb to Timber. Then I go back to my just-attack strategy.

If you're an uber twink of FF8 like me, there aren't really any tactics involved in the game; you get stats way up high and then you usually just focus on attacking.

EDIT: Once I get my crappy GeoCities website up and going, you can find out how to do such things.