Rapid regeneration? This isn't a comic book. The best that you will get is this:
Hello. I wanna rapid regeneration. How can i do this for itself? I cut my finger before 1 day ago. But its not losing easyly. Please answer my question if you know.
Well, there's a quicker way pilgrim ! One touch and it'll heal right up!
Unless you are like Sudo the Dragon, and not human, regeneration is going to take a week or more depending on how deep the cut. Your best bet is to keep it clean, and try not to reinjure it.
Healing / regeneration / wound closure is a programmed response from the body.
You can maximize the environment that the process takes place in by staying healthy in general, and by proper wound care.
Beyond that, there are no known techniques to speed up the process that I am aware of.