Most content items (pages, items, etc) will have a "Version History" tab located within the content item window.
- Select the page/content item you would like to restore
- Select the "Version History" tab
- To revert back
- Determine which date and time you would like to revert the page/content item back to, then select "Revert"
- A window will popup confirming if you are sure you want to revert back, select "yes"
Example: "version history" home page