Well, that depends on your age and situation, flexibility, and what kind of artist you're looking for.
If you're an adult with money to spare, you could commission an artist. Prices can range from $5-$200+ depending on the art you want and the artist's experience. Lots of artists post their rates on Insta and Twitter, or list their services on Fiverr (or other platforms I haven't thought of). This is the way to go if you have a solid idea and don't want an artist to suggest changes, just provide visuals.
If you're a kid (too young for Paypal), broke, and/or open to collaboration, you could try to attract a co-creator to work on your story with you. They'd potentially have input on story as well as design, and ideally you could share ownership of the ideas. Tbh it's a hard sell to internet strangers, but you might be able to find someone on the Tapas discord who's a good match for your interests and skills.