Terminal window: “sudo vi /usr/share/xsessions/chromeKiosk.sh”  This should bring up another vi window for you to insert the following code:

xscreensaver -nosplash &
cat ~/.config/chromium/Local\ State | perl -pe “s/\”bottom.*/\”bottom\”: $(xrandr | grep \* | cut -d’ ‘ -f4 | cut -d’x’ -f2),/” > ~/.config/chromium/Local\ State
cat ~/.config/chromium/Local\ State | perl -pe “s/\”right.*/\”right\”: $(xrandr | grep \* | cut -d’ ‘ -f4 | cut -d’x’ -f1),/” > ~/.config/chromium/Local\ State
while true; do chromium-browser %u –start-maximized; sleep 5s; done

If you would like to disallow access to the URL bar simply insert “–kiosk” between %u and –start-maximized as shown in the sixth picture on this step.
A few people commented that the inclusion of the “–incognito” switch at the same place as “–kiosk” goes makes it so that you do not have to worry about making the Chromium user profile read only.

After you have created these two files run “sudo chmod 755 /usr/share/xsessions/chromeKiosk.sh” in order to make this script executable.