use social media to promote your business, i also reccomend using shopify, and remember that it takes time. it's easy to get ahead of urself. also try to get some friends to take pics of them with your clothes on (pause), to showcase the designs.
DM me on instagram, @venace.clothing, my brand was an experiment as my parents didn't support me in the end, I can't help much with marketing, but I got knowledge with photoshop and I'm willing to help you a bit for free.
Define Your Brand Identity: Determine your brand's unique identity, including its mission, values, target audience, and overall aesthetic. Consider what sets your clothing brand apart from others and how you want to position it in the market.