Most healers use Enemy these days. If you are just getting started with it, you can configure it to show a few key things:
- Show the HOTs you have applied to people. This way you can keep track of who has what and when to reapply. See this thread for details on how to track the main HOTs for your class.
- Dispellable DOTs. This can just be shown as a red dot on the unitframe so you don't need to worry about what the affect is specifically. You just know that you can cleanse it.
Once you get more comfortable, you can add additional customizations. For example, you can enable click casting (note: hover casting doesn't exist in this game; only click casting involving the Left Mouse Button seem to work...ie Shift+LeftClick). You can color code the unit frame based on role (Tank, DPS, Healer). You can add additional colored dots to track specific things. You can have it sort your groups by Tanks, DPS, Healer.
One way to get started is to use the Enemy configuration that comes with VinyUI. You don't necessarily have to use VinyUI...you can just copy the Enemy configuration settings files. VinyUI pre-built configurations for both Order and Destro healers. Or you could just use VinyUI, which includes a bundle of other useful addons.