It's very important to preview the projects before you go live. You can use the preview links and send them to other deveices by copying the URL with the preview parameters. If the preview parmeters does not show in the URL you can re-add them by choosing the variation in the preview bar at the bottom left (see image below).
Preview shows exactly how the changes will look when the project go live so test this on all devices / browsers you will run your project on to be certain it works and looks the way you want.
In preview you can also check that audience is set correctly and that your goals/KPI's work.
