(only to women)
Step One: Grow old. Doesn't matter how handsome you WERE.
Step Two: Do not become wealthy.
Step Three: Get a fat belly.
At this point, you are virtually invisible to women.
Exceptions:
1. Staring at boobs: for some reason, if you stare directly at a girl's boobs, she WILL notice you again and be able to see you.
2. Make any sort of mistake (especially look at another girl's boobs) - your wife will notice you.
3. Try to relax. Your wife will immediately notice and your spell of invisibility will break and have something for you to do/take her some place.
WHAT CAN YOU USE THIS SUPER POWER FOR?
If you were a teenager, you could sneak into girl's dressing rooms, or find some way to perhaps subvert crime with it. I don't know. It never worked back then for me.
However, the answer is absolutely nothing other than serving to remind you that you used to be cool/desirable and /or making you think that you used to be cool/desirable even if you were not.
Note: this power does not work when your daughter/wife needs/wants money. You cannot hide, in fact they can track you any where you may be hiding.