For a support only cleric you will need max charm (400) the rest to Int (304). Get bonfires, salamander flames, and mana flames all maxed. No attack skills at all if you want all the support skills. Get all passives related to buffs (Int and such), get all charms and chants maxed. Get the IM Res, not the regular skill. Get Purify and the IM Purify AOE. Get Integrity Unique. Summoners Gift Unique. And get whatever IM Passives you can. You will need as much charm gear as you can afford. For a max level FS Cleric to get max buffs, you will also need a Legendary Wand for level 200. That covers most of it.