As name implies, a default site family is selected in default manner when a user starts page of the Wizard. Every plan contains one default site family for the plan. You may follow below listed steps to set a default site family.
- In the navigation pane go to the Users and choose plans
- Click the name of the corresponding plan in the list of plans on the Plans page
- On the Site Families tab of the plan editor, select the required site family and click Set as Default.
- Click OK

