I need a designer for sportswear and fashion clothing

Hey, I am thinking of having an online business for clothing mainly. I am a big fan of fitness, so I am leaning towards sportswear for both men and women, but at the same time i want to have my fashion clothing store starting with hoodies or shirts and I genuinely like stylish clothes, my type of stores would be iamgia, tigermist and outcastclothing. So I would want a designer that helps me design styles like that. Thanks!