During the sign up process you were prompted to create a User Name and Password. You will need these each time you would like to login to your Zenfolio account.
You can login and logout from the main page: Zenfolio.com
If you have any problems logging in see the Help section on Resetting your Login and password.
Note: Most web browsers will work fine. In case of any problems, refer to the list of recommended browsers. Cookies must be enabled in order for login to work.
To Logout simply click Logout next to My Zenfolio at the top right of any Zenfolio page.