Before making an event live it is a good practice to check all points.
Once done with all check points can make your event live with below steps.
Click on "Event Info" located on the left as shown in below image.
On "Event Information" page find "LIVE" located as shown in below image
Your event will be live for ticket selling.
Now, visit your event page to do test purchase as a buyer, making sure payment integraion works successfully and ticket order gets completed, tickets are getting generated.