As a cleric, there is a single-target heal spell. I have been able to use it by pointing my mouse over my teammate and pressing the bound key. Is there a way to target this heal other than by pointing at a teammate? I ask this because sometimes there are a lot of teammates standing next to each other and it becomes hard to target one specific teammate.
Normally you can lock to a target by pressing down the left control (LCtrl) key. That's a bit cumbersome while in a large battle. Instead, you can reprogram the game to have the control key, or any other key you find convenient, toggle between locked and unlocked (press/release the key once to lock, press/release a second time to unlock)
/bind <key> "++HardTargetLock"
You insert the key you want instead of
Personally I used a key I don't normally use during game play, and then programmed a button on my game mouse to press that key. That lets me target / untarget someone by pressing that mouse button.