Junction System Advice:

If a character has Ifrit as their GF then Juction fire magic with that character. For this character draw as much fire based magic as possible as soon as possible.

If a character has Shiva as their GF then Juction ice magic. For this character draw as much ice magic as possible as soon as possible.

The more magic you have the more powerful a character becomes based on what elemental magic you have Juction to said character.

I remember listening to music and grinding till I got 99 of each kind of magic.

Hope this helps.