I think its better to be a battle type Acolyte first.
You can use the supportive skill to yourself while killing the monster. Maximize these skills(Agility Up , Blessing , Heal and Teleport maybe if you want)
The best gear for new player is Eden Group Equipment. By doing this quest http://irowiki.org/w...uipments_Quests
Talk to Instructor Boya & Instructor Ur at Eden Counter.
For leveling, the best option is by doing the Bounty Board Quest http://irowiki.org/w...ty_Board_Quests I think this one is the best for me.
Alternatively by doing the Eden Group Leveling http://irowiki.org/w...Leveling_Quests.
From your word "Supportive Class" so I guess you gonna be a priest. Change to Priest or Monk at Job level 50 by doing the Job Change Quest. Refer irowiki.
When reach level 70 you can start doing http://irowiki.org/w..._Turn-In_Events by talking to Gramps at Eden Counter. Here you can find a party that need healer (Your Class). From here you can be a full support type. These skills are useful at this moment for party buff (Magnificat, Angelus, Gloria). Take note this is skill for Priest.
This is just my suggestion and there's gonna be a better suggestion from senior player.
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