The dealer should have provided documentation and quick start guide for OnStar, but here you go:
To store a telephone number and its name tag in the system, do this:
Press the white phone button.
OnStar will respond with ‘‘OnStar ready.’’
Say ‘‘Store.’’
OnStar will respond with ‘‘Phone number to store, please.’’
Say the entire number.
OnStar will repeat the number, and then say ‘‘Yes or No.’’
Say ‘‘Yes,’’ or say ‘‘No’’ to try again.
OnStar will respond with ‘‘Name tag, please.’’
Say the name that you want assigned to that telephone number.