Your probably wonering why I made a whole page for this. Well this is what made me finish the game. I would have never done it without it. Ok well look at this map:

You need a Black hole. You can get one from a wendigo or a Gesper after battle.
When you have that and you have the ragnorak. Then you can go to one of the islands (I preferred Hell) and come into a battl with Quistis HP low and letta rip with it. And your team gets all the EXP. But Quistis might die alot so have Revive and life ready.
The bad thing is that with Squall always having to be in the party and Quistis as well then after Squall, Quistis and another character are at level 100. Then it will be one character leveling up by themselfs which takes longer. But they do get more of the EXP. So if your a die-hard gamer then you'll do it but if your not that bothered dont go there.