"Master Xornn," said Jakonis, beginning a question during his training, "you teach me of controlling my enemies and manipulating my environment..."
Xornn made no indication of hearing Jakonis, but nodded to no one in particular as he looked over the rocky crags of the Dreadlands.
"But you say very little about my accentuations I've learned... when do I cast haste on whom? What is more important, mana or speed when my own mana is tight? Should I use my armoring spells of protection?"
Xornn continued to scan the edges of the rising mountains, apparently occupied with whatever he was looking for. Jakonis thought of repeating his question, but knew that somewhere inside, deep down, Xornn had already answered... it just hadn't gotten to the surface yet. When Xornn snapped his gaze to Jakonis, he felt himself flinch, and bit down on his tongue to hide a smile--master had such a flare for the dramatic.
"Does your fighter have haste? If not, grant it upon them. When both mana and haste are lacking, are the tanks fighting--or are the healers low on mana reserves? Cast accordingly. If you aren't doing anything, and your armor spells are faded, cast them." Xornn looked at Jakonis sternly. "Really, apprentice, you have a habit of answering your own questions."
This will be a short section, as there's only one real rule to buffing people... well... two.
First, get crowd control done. Second, if the buff in question will appreciably aid the target, cast it. Mana regen is always good for anyone that uses mana. Haste is a must for those in melee combat. Magic resistance is a given for yourself, and if there are casters among your enemies then your group needs it too. Intelligence and Wisdom buffs raise maximum mana, but aren't terribly important when mana is tight, because they aren't doing anything then. Armor class buffs can ease the clerics mana load when needed, and things like vision or stamina regen are just spells you cast as needed.
Buffing is recognizing a need or spot to be improved, and casting the spell to accomplish that. The only other trick to buffing is remembering when it needs refreshed, and planning mana around that. For most spells, you can buff yourself with it first so you get a reminder to refresh it. Spells the whole group will receive or that have high mana cost (that you need to med up for--like hasting tanks) should be tracked on an egg timer or such to remind you when it's time to start getting ready for that buff session. Buffing isn't hard, it's just an important priority--which is why many enchanters can get by just on buffing alone.