Anyone who has cut off their parents, how did you do it?

This is my first post on a subreddit like this, so I apologize if this is incorrect in any way.

I am graduating High School soon, and when I do I plan on leaving and never coming back. I want to cut them off, but I have no idea what to do or where to start. I am also terrified, I am afraid of what they will tell people or guilt me into not doing it. I don't know what to do, and I could use any advice or guidance you have. Thank you.