To log in to your Evergreen online dashboard, go to the following url:
The page should look like the screenshot below, with a place for you to enter your login information:
Do you have a master login for multiple accounts?
After logging in, you should see a screen with all of the locations that you manage that allows you to select which one to manage:
Once you are logged in to a particular account, use the dropdown on the upper right hand side of the dashboard to switch locations at any time: