If you have a general question on how to distribute and submit a FomrsCentral form, please take a look at this tutorial:
Section: 'Preview your work and test your form or survey' and 'Easily distribute forms and surveys'
After you have authored a form, select the Distribute tab and simply select "Copy Link" button and then paste the link on another browser window url address. Navigate to the form link and fill out the form and click on the Submit button. In FormsCentral View Responses, you will see the response just submitted.
Hope this helps,