Create a date field if you want to send autoresponders to your subscribers on a specific date like their birthday. Or, lets say you want to collect birthdates from your subscribers. You have to use forms and you are going to need a custom date field.
To create a custom date field, go to Subscribers and click any list. In the list, go to the Custom Fields tab. Add your settings and just like that your new date field is now live. You will be able to use that date field for specific autoresponders and when collecting user data with forms. Quick note: the difference between default fields and the ones you created yourself is that you can delete or edit your own fields, but you can’t delete or edit the default fields.