Create and use the Forward This eMail Form
https://www.blackbaud.com/files/support/guides/sphere/Create_and_use_the_Forward_This_eMail_Form.html

Configure the Complete Initiative Information page for a Forward This eMail Form
https://www.blackbaud.com/files/support/guides/sphere/Configure_the_Complete_Initiative_Information_page_for_a_Forward_This_eMail_Form.html

Configure a form's layout
https://www.blackbaud.com/files/support/guides/sphere/Configure_a_form_layout.html

Add a Forward This eMail Form to mailing content
https://www.blackbaud.com/files/support/guides/sphere/Add_a_Forward_This_eMail_Form_to_mailing_content.html