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