Correct me if Im wrong but doesnt it mean at the beginning of ur turn/or whenever. You for ex: Give Bishop a click of damage to heal Nightcrawler? or is it something else?

The only limitations on the X-Men and Teen Titans TA are these:

Both figures must be adjacent

Both figures must have the same TA (Wildcards do count)

It must be your turn

You must have at least 1 unused action from your allotment of actions

You must heal one figure 1 click of damage and the other must be dealt 1 click of damage

The figure that received the damage must be given an Action Token

After that, everything else is fair game.

Hope that helps (and makes sense).