Upon initial login, with the 'Job' selected, click the magnifier.
On the upcoming screen, navigate to the bottom left corner, and under the 'My Favorites' tab, there should be a link named 'Switch 360 Role'. Click the link, and a new page will open with the available additional roles under your 360 account.

To switch roles, you can right-click the link and select
'open link in new tab'
-OR-
'open link in new window'.

That way, the view under that role will not overwrite your login, and you will not have to log out/in again. Just close the new tab/window, and you will be back on the window with your initial login.
On the top right corner under  'Logged in as' it will indicated the other role that you are viewing.
Using the menu, you can navigate on the various pages of the secondary account you are viewing
To return back on your own role, you will need to close the new tab/window where you were viewing the other user and return back to main page with the list of available roles.

Click your role and will return back where you logged in