Fastest way from what i know is to order lowryder seeds they start flowering once they pop out of soil and grow to be around 15 inches. I think it takes like 8-9 weeks.
How soon you want it to happen? How much money you got? Gotta be stealth or no worries? Indoors or out?
You should probaly put a bit more thought in your questions on this forum. Lots of people willing to help. If you have some idea of what you are wanting to imbark on. And maybe do a bit of homework? Best of luck, grow AMERICA GREEN