It can be helpful to occasionally create backups of your guides because a deleted page or guide can not be restored once content is deleted. You have to recreate the content. Fortunately any assets that had been added to the page will still exist in your assets library (Content > Assets). That means you can reuse those assets without having to recreate each one from scratch.
Backups are automatically created when a guide is deleted and any guide owner can also create a backup while editing a guide by clicking on the Guide Information menu under BACKUP/EXPORT, select Create HTML Backup.
To view all HTML backups that have been created (manually and from deleted guides):
Create an HTML backup of a guide
Viewing HTML backups