Just got melia. Read the guide and i still don't understand what im supposed to do with her lol.
Very basic rundown:
Using her summon skills (Lightning, Water, Fire at this point) will cause her to create an aura. These will give you a buff centered on Melia. When you release an element, it does an attack on the target and removes the aura. Sometimes you want to keep the aura up, sometimes you just want to attack.
Lightning - Boosts Ether, when released does large damage to single target
Fire - Boosts Strength, when released does medium AoE damage plus blaze DoT
Wind - Boosts Agility, when released does medium AoE damage
Water - Healing over time, when released leeches HP from target to Melia
There are others that you will earn as Melia levels up. Be sure to look at your Tutorials for more detail. Not all of them come up automatically.