With a free text custom field, customers will be required to enter text - for example, notes, comments - in a field.
1. Go to Settings>Customer Details
2. Go to the Custom fields tab
3. Click on the New field button
4. In the Type section, from the Type  scroll down menu, select the user enters free text (notes, comments, etc)
5. In the Application section, tick the customer making the booking  and/or to the participants  checkboxes to set when the field should be applied
6. In the Details section, input the Name  and Description  of the field.
7. Tick the Multi-line  checkbox if customers input text in multiple rows.
8. Tick the Required  checkbox if customers must enter some text to complete the booking.
9. Tick the Public  checkbox if customers can see this field.
Custom fields for participants will be asked during the booking process if you set that you want to Ask for the details of every participant: