There are two main ways that you can backup your server: 1) You can use our panel's backup feature by going to the left side of the panel, clicking on the files dropdown menu and then clicking on Backup. If you click on the Start button it will backup a copy of your world file only to the root directory in a zip file. This does not backup your plugins or anything other than the primary world. You will not have access to these files if you stop paying for your server. You can click the Restore button if you ever want to replace your current world with your backup world (in case you get griefed)
2) You can download all the files to your computer using Filezilla. This is the recommended way as you will save all of your files and still have access to them even if something happens to your server (griefed, stop paying for it etc). Follow the tutorial here: https://ownagehosting.com/billing/knowledgebase.php?action=displayarticle&id=64