[About the design part? Not a clue. But, actually...]

Do you know how to sew? [She figured it was a fair question, given his father's profession and his admitted role as a sometimes model.] Because that's an even handier skill to have. Clothing made from scratch is always cheaper than the already made kind. And you can choose your own material. Even if you can't do that much, being able to mend is still useful.