Once you log in to your CD account, from files and discussions in a workspace, select any file and click the Proof Action->Create button.
After you create your proof the file will open in the Ziflow proof viewer.
Sharing Proofs:
To share this Proof after its created, click on Proof Action -> Edit
In the Proof settings window you can add the email and choose permission.
In the Proof Settings window you can also edit permissions and notifications.