You can easily create popup form. Just follow the steps:

  1. Open your form.
  2. Go to Form settings.
  3. Enable Popup
  4. Specify button text or just text

Web-form popup settings

The result is:

This is my new form!

New textfield
New textarea
New number field
New email
New phone
New time
 :  : 
New date
 /  / 
New checkbox field
New radio field

New selection field
New file
Select files..
Maximum file size: 10 KB
Maximum files count: 3
New rating

This is HTML field.

Use clean markup!

New table grid
New hidden field

You can use Web-form buttons.