Login to your club control panel.
Click the 'Membership' tab from the left-hand menu.
Click the 'Fields' tab from the left-hand menu.
Locate the custom membership field and click on the title of the field.
Scroll down to the Club Signup Form section.
Tick the 'Show in signup form?' option
In the expanded options, tick the member roles you wish to collect the membership field information from.
Tick 'Is the field mandatory?' to ensure the member is required to provide the information as they apply for one of the roles ticked.
Click the 'Save' button at the bottom right of your screen.