Starting a Fashion Brand/Company

Hello all. I completely adore fashion, and haven been for a while. I love how it sets new trends, and vibes and it can completely change how a person can appear to one.

Now, I'm not really paving this to be a guaranteed career path, but I am starting to take Graphic Design in September for college, and I have a specific brand I made up in my head, and i have the visual layouts and stuff pictured in my head, and it's a really unique style of clothing for men/woman and it is heavily based on 80's "stand out" colors.

Now, where would one start with this idea?

I know you guys aren't fashionista's or anything, but can someone maybe guide me in the right direction, or maybe some warnings/etc about this career path.

Thanks a ton!