You can sign up for cflow by clicking the “Sign Up” link on the Cavintek website.
http://cflow.cavintek.com/cflownew/login.aspx?signup=1
Once you click on the 'Start Free Trial' button , you will see the below success message
and will recieve an invite email to your email id.
The sample invite email will look like the one shown below:
Click here to know how you can do a 'Sign in with Google' if you have a 'Google Account'.