ROGAINE AFTER 12 HOURS REDDIT - DOES IT WORK?

Yo dudes, so I'm thinking on using Rogaine. Heard some talk about it working after just 12 hours, but that seems kinda crazy, right? Anyone else try this magic potion and actually see changes in that time frame? Hit me up with your experiences. List a few things I'm thinking about: What much Rogaine do you gotta use? Is it important to apply it