Two macros. The first to get the target you want to CC. The second preforms the action.
/cast [target=focus]
In a new Macro:
/cast [target=focus] Polymorph/Fear/Banish/Shackle/ETC
The first macro locks the mob that you want to CC. The second will select the focused mob and preform the selected action.
So, if you are dotting a mob and then click the second macro after you have set focus to one. It will turn and fear that mob or sheep. Whichever skill you put behind it. This makes CC a shit load easier. It also works with enslave or any cast in general. It is just more practical to use it for CC but is not limited to it. You could actually multi-target and DPS with this as well. By setting things as Storm Strike or Frostbolt to the next target on the kill list. And boost some DPS