The importance
Getting a manufacturer is the most important part of creating a brand. This is where you will get your designs put on the piece of clothing you want. They create samples for you on whatever design you can make up. You can find manufacturers on Alibaba.com. Once you receive your sample you'll be able to create a bulk order. A bulk order is however many pieces you want to sell. It is important you have a good bond with your manufacturer. They will be making your job a lot easier.
Here's a more in depth explanation of what to do when choosing a manufacturer