By default, the contact details you enter when you set up a new client will be the "Primary Contact" for that client.
Click on the green New Contact button, and you will see the Manage Contact dialogue box.
Fill in the fields for the new contact, and select the relevant boxes if you want this contact to be set as any of the following:
- Primary Contact - used for everything unless you have other contacts set up
- Accounts Contact - this is the contact that will be used by default for invoices
- Artwork Contact - this contact will be used by default for artwork
- Bookings Contact- the default contact for bookings.