Opt-in Channels - Fields Tab
By default, your campaign has subscriber fields.
Select the fields you'd like to include in your web form by selecting the checkbox to the left of the field name.
To make a field "required" select the required checkbox to the right of the field name.
Please note: if you embed the web form on a web page outside of IC you need to use the default fields such as First Name, Last Name, Email, etc. If you use custom fields for name, email etc. the system will not properly receive the information and the autoresponders will not be sent out. Both autoresponders and Zapier are dependent on the default fields.
You must launch & Save the web form builder, found on the next tab, for changes to materialize.