Hi, KLC. This is a great question. 🙂
First, we always encourage user to make a complete backup of their site before updating plugins. Please take the time to do this in case anything unexpected happens after the update is complete.
When updating to the newest version of WooCommerce Tickets, you should be prompted automatically, assuming you have your license key installed. Otherwise, you’ll want to rename the plugin’s folder in your backend file manager, and then upload the new version using the admin interface. (The admin interface will not allow you to overwrite the folder of the existing plugin.)
All the data is kept in the database, so you don’t have to worry about losing data when updating the plugin versions.
Please let us know how it goes! 🙂