How to create repository pattern for multiple tables (Header & Detail)

I am new to repository pattern. Can anyone help me on how to create repository pattern & service for 2 tables.

Eg. I have a User Creation screen which have user information and multiple role details. Both data will inserted in a different table. For this scenario how i can create a repository pattern and how to call it.

Note : I am using ADO.Net for the DAL.

Thanks.