A scheduler will contact you. On the 1st of every month, their scheduler makes assignments. You receive an email and you log in and accept or decline the assignment. You can also check the website for "orphans." If someone declines a shop, it goes on that list, so you may be able to pick up a shop that someone has declined. Other than that, all their assignments are auto-assignments and they you decide if you want it.
This is a really great company to work with and I like them. Ardent is the biggest reason I keep doing these shops, because I am on the fence about the food. I find the client's burgers just okay and over-expensive. There are better burgers around so I only eat these because they pay me.