The healers, here I wanted to do something a little different. I wanted to make something incredibly simple. So what I've done is made a build that uses the exact same everything except class skills. Gear, Champion points, Weapon/Guild/World even food and potions are the same. So no matter what class your on you'll be ready to handle any group situation with ease. These builds push everything you need as a healer in the most common situations, and even in "PUG" groups!
Your first job as a healer is to obviously heal your team.
Second as a healer your in the strongest position to buff your team with all sorts of things, from making them take less damage, to even do more damage.
Third as a healer your in a fantastic spot to debuff the enemy only where you can of course.
You'll find yourself "over healing" your friends a lot of the time these are the perfect opportunities to reapply buffs to friends or target those bosses and help out the tank with some debuffs.