If your organization is using a sandbox or test environment to access CPQ (for example, if you are doing user acceptance testing), go to http://test.salesforce.com/ instead.
From the toolbar at the top of the page, click Login.
Enter your user name and password, and click Log in.
Navigate to Apttus Proposal Management to access the proposals.
In Salesforce Classic: Click the App Menu
In Salesforce Lightning Experience: Click the App Launcher.