Make a .bat file for running SSMS with Windows Authentication as a different user other than the one you are immediately logged in as.

Put something like this in the .bat file:

RUNAS /user:dmzmgmt\tjaeschk /netonly "C:\Program Files (x86)\Microsoft SQL
      Server\130\Tools\Binn\ManagementStudio\Ssms.exe"

 
 

When you double-click the .bat file you will be prompted at a console to end your password.