This guide walks through the installation process, offering several different options:
It is not a problem and if you Log Out of the desktop, you can choose which desktop you log in on from the login greeter screen.
So going from Desktop to Desktop is as easy as choosing which one to log in on. I have Z16 with gnome and installed Mate, XFCE4 and Cinnamon desktops on it. I switch between them on an as needed basis.