From the Dashboard, click on CRM and select Lead Layouts & Fields from the drop down.

Click on the Fields Tab

Click on the Add Lead Field button

Select the Radio Button for Date or Datetime

Configure the following

• Field Number - Assign a Field Number - There are 10 fields that can be used as Searchable options in reporting - They are marked as Searchable.  Use these fields carefully.  
• Field Label - Enter a label to be used on displays, page layouts, reports, and list views.
• Field Name - The Field Name is an internal reference and is used for integration purposes such as custom links, custom s-controls, and the API. Be careful when changing the Field Name as it may affect existing integrations.
  • Note: Field Name cannot be ending with an underscore
• Description - Additional info about the field (Optional)
• Help Text - This text displays on detail and edit pages when users hover over the Info icon next to this field.
• Status - Either show, hide or disable the field.
• Required - Always require a value in this field in order to save a record.
• Default Value - If this is set, the value entered will auto-populate the field.

Click on Add Field Button

After adding the field, additional Field will show.

• Date Format - Select the Date and Time Format for this Field

• Required Statuses - This feature will allow Admin to have a required status or statuses for this field. The agent will not be able to select the disposition of the lead without using the required status or statuses of the field.
  

Select the status and click on the left arrow button to add the status on the Disposition Statuses this field is required for.

If the Agent selects the disposition Appointment and leaves the field blank, this popup will appear

Click on Save Changes to apply the settings.