Instructions
Getting into Battle
Turn your low-level characters into mimes in the "Job Change" menu.
Ensure that some of your higher-level characters can use abilities in battle that can keep an enemy from acting. For example, Mustadio's "leg aim" and "arm aim" abilities can keep an enemy alive but unable to act or move. The Time skill "Stop" works also.
Wander the World Map screen until you enter a battle.
Gain Levels in Battle
Choose your mimes and your high-level characters for battle, since the enemies in random encounters match the average level of all your characters.
Kill all but one enemy in battle and disable it. Encircle the remaining enemy with your mimes.
Make actions against the remaining enemy with a high-level character. A few options include a weak attack, which requires equipping a weak weapon. Periodically, you will need to heal the enemy to keep it from dying. The mimes will repeat the action every time and reap generous amounts of experience points.