How to make my own card-making business?

[Rainbows are Love]

I'm wondering how I can make my own business making cards for people, cards such as, birthday, cards, christmas cards, invitations, etc. I'm good with making cards on Microsoft Publisher and adding special fonts, pictures and designs. I'm even in charge of making flyers at my high school. I want to make a card business during college (I'm majoring in paralegal btw) so I can make some extra money but I do not know what first step I should take in making my own business. If you know, feel free to answer!