How to book ASC appointment in Mexico

[Chinni6]

Hi All,

I am planning to go Mexico for my H1B renewal. So i need to book ASC and USC appoinements.
Are they two seperate appointments? Will they be booked together? If I go to the usvisa website it gives me dates to book the USC appoinement. Then where to book ASC appoinement?

Appreciate your help.

Thanks
Chinni