For every ticket bought, you can ask users details about the ticket holder.
In order to do that, you have to create the fields of the form that will be later shown on the product detail page.
Go to the product edit page, click on the Fields tab, and add all the new fields you want to show in the form.
There are 6 types of field available:
If you want to make the field mandatory, check the Required box.
The fields will be shown in the event detail page, as shown in the following image.
The same information form will be replicated for the number of tickets ordered.