By default, the GDPR consent requirement is applied against standard Contact profile page fields: Address, Email & Telephone number. As needed, use the control panel custom field settings to apply the GDPR requirement to other Contact custom fields.

To apply the GDPR requirement to Contact custom fields, navigate to the control panel > click 'Contact custom fields' on the Admin panel > select the desired custom field  > toggle the option next to the GDPR text to apply the consent requirement against that field.

Thesymbol will now display in front of the field in the Contact profile page to indicate the GDPR consent requirement is applied.