The first time you are logged in on this website, you have already an available farm linked to your profile.
This is the TheDemoFarm, wich was presented during the last meeting in Paris. You can select this farm using the control center.

While you are inserting your own data but you have a doubt, you can switch the current farm and verify you're right.
If the doubt remains, you can add a question to the F.A.Q..