Setup the Application : Define Member Packages : Define Package Add-ons : Add Custom Fields

Add Custom Fields
The membership application form may be setup to receive input from applicants into Custom Fields that are created by you. Create the custom fields on the General tab in the Members module. Click Add/Edit Custom Fields. Any custom fields will display here as options to be included on the membership application form.
1.
On the Member Application Form Setup screen, click the Custom Fields tab.
2.
Visibility selections:
Optional will display the field on the website but will not require the applicant to enter information into the field.
Hidden will not display the field on the website.
Required will display the field on the website and require the applicant to enter information into the field before submitting the application. These fields will be marked with an asterisk (*).
3.
Click Save.