Answer:
Best tip: You don't it has to wear off.
Henna is a stain so it is really hard to remove.
You can:
1. make sure to was where ever the henna is.
2. use exfoliating soaps or a pumas stone.
3. use bleach and a q-tip and scrub the henna. Be sure not to leave the bleach on for too long a minute or so will do. Repeat every hour/until henna has faded or until the henna no longer fades. If area begins to itch or peal WASH IMMEDIATELY!!!! I cannot stress this enough.
4. use make up to cover it up
Best tip:
Wait for it to fade