There are multiple ways to manage simultaneous logins with different Office 365 accounts. Two of the most popular are – Use InPrivate browsing and Google Chrome Account management.
InPrivate browsing will not store cookies, Temporary Internet Files (also known as cache), or other private data components on your hard drive. Your browsing history, saved passwords and autofill form information are also permanently deleted at the close of your browsing session.
To use InPrivate browsing in Internet explorer First, open your browser. Click on the Gear icon, also known as the Action or Tools menu. When the drop-down menu appears, hover your cursor over the Safety option. A sub-menu should now appear. Click on the option labelled InPrivate Browsing.
Please note that you can utilize the following keyboard shortcut in lieu of this menu item: CTRL + SHIFT + P.
InPrivate browsing also available in Google Chrome. It’s called Incognito window and accessible via CTRL + SHIFT + N shortcut or Chrome menu New incognito window.
Another option, Google Chrome account manager will probably be more convenient as it can remember your credentials for multiple Office 365 tenants. The idea is to set up new google chrome account/user for every Office 365 tenant.
To add new user to Google chrome browser - go to Chrome menu and choose Settings. In settings menu, find Manage other people and click Add Person. When you add new person, you will be able to open Google Chrome as that person and can log on to Office 365 with different set of credentials.