you discuss with them the details about what you want your personalized handle to look like
they quote you a price
you move forward from there
Here are some tips:
Think of this as hiring an artist to create something for you. You have to work closely with them to deliver your vision.
it is absolutely illegal for them to sell you anything even closely resembling an exsiting trademarked or copyrighted image. meaning, they cannot sell you shrek or elsa. your influencer handle must be unique.
expect to pay $80 or more dollars for a fully customized (bespoke) creation.
if the cost of a customized handle is more than you think you can afford, you can always buy a blank kit and customize it yourself. we have a page dedicated to customization ideas.