People On The Grid
Tidus- You will notice that Tidus's section is based on speed, travel all the way untill you come out to Yuna's section. At this point go over to Wakka's part to make Tidus into a hard hitter, finish that then continue on into Auron.
Yuna- Yuna's section is based on white magics, when you reach the end of her part (Holy) jump back to where she started and learn Auto-Life, after that go learn Full-Life, now you have a shit load of Mp so learn some of LuLu's most powerful black magic.
Wakka- Wakka's part is based on hard hitting and statues effects, anyone with high strength should come over her and learn some of those. When you reach Triple-Foul continue on into Auron's section.
Auron- Auron's part is based on hard hitting and lowering enemy stats. After his part is done, you shoul go over to Tidus's area to get some speed.
LuLu- LuLu is based on Black magic, after she learns Flare take her to Yuna's pat to get some white magics, with all that Mp she could use Holy. Don't even think of taking her to Wakka or Auron, phsical attacking is not her department, not even to learn it.
Rikku- Rikku is based on Use/Steal items durring battle, Rikku's Use should be taught to someone you use a lot, so you can keep up with your Al'Bhed potions. Rikku can be taken anywhere when shes done with her part.
Kimahri- Fury Kimahri starts off in the middle of the Grid, you can take him into anyones's part (except Auron's) early in the game.
-Ultima-
You may notice that the grid revolves around the ability Ultima, which is a very powerful magic skill. Ultima is surrounded by Lv.4 locks. Send Kimahri back to teach it to him because he will be very easy to get back. Teach this to anyone you use a lot including Yuna. I recomend Yuna, Wakka and Auron.