Are you using FormsCentral in a web browser or are you using the "Desktop application" that is included with Adobe Acrobat Professional XI? Knowing that will help me get you going...
I'll start by pointing you to some resources to learn more about using FormsCentral (these are focused on using FormsCentral in a web browser, I'll give you some additional information if you are in the Desktop application):
How to create a survey or form (set of tutorials):
Help and tutorials: