Once in the Client Information screen you'll see the Client Info Settings area. By clicking "Edit" on this section you can customize what your title bar says as well as add some header text and change the label on the "Save" button. By clicking on the "Add or Remove Fields" you can customize what specific information you want to request for clients to submit. Here's a close up of this section:
You can learn more about editing your Client Info panel settings by reading our documentation here.
You can also learn more about adding or removing fields by reading our documentation on defining field labels.