Have an Answer?
If you are new to the game start off researching clothing designers like John Varvatos, Alexander Wang, Vera Wang, etc. study these designers find commonalities that made them successful. The next step is to network, network, network. These groups will help you out...Fashion Denver, Fashion Group Denver, and Denver Design Incubator.
The best thing any entrepreneur can and should do is study great entrepreneurs and realize it is I easier to learn the tough lessons early on in life. Every great or inspiring entrepreneur has a business coach and an accountability partner and every business coach and every accountability partner has one to back them and learn from.
First, find customers. Show them drawings of your designs or, better yet, get samples made. Then reach out to people you think would be interested. You might find them at school, among your friends, on social networks, online at places like Reddit, or other places you can think of. Get three people to pay for your idea.
Next, fulfill those orders. Find a local tailor to make your first clothing. Deliver them to your customers. Get their feedback. Ask lots of questions until you have a good idea for what will make your customers happy. Don't worry too much about profit margins at this point.
Iterate on the above steps a few more times until you feel like you have something that you know people want, and you know how to reach them. Then, and only then, it is time to scale. You'll need to find a manufacturer who can produce the garments in large lots, and you'll need to figure out how to acquire many more customers affordably. That means distribution, whether its retailers (online or off) who can distribute your physical product, or online influencers who can distribute your message/story to drive people to your website.
Good luck, and let me know if you need more help.