razor's got it.

I do this setup, and have the tank as the master. The DPS and healer are the slaves.



The way I do it is i have the main dps button (2) hitting with the left hand. I use the mouse to move/ reposition the paladin. I use a key closer to the mouse (7/8/9) to handle heals. When I need heals I take my hand off the mouse and hit 7 (greater heal on tank), 8 twice(PoM then renew castsequence on tank) or 9 (shield then renew castsequence on tank's target, used for spot heals). If i need aoe heals, i hit alt+4 which is prayer of healing. If i need small AOE heals, i hit alt+3.

In PvP I give my priest (healer) a slightly different set of keybinds. 2 (main dps button) casts circle of healing, basically a spammable aoe party hael. 4 (secondary dps button) casts smite on the tank's target. This way I can get the preist to dps if needed, or to just spam heals otherwise.