You can set an expiration period for an item so that the item automatically expires at the specified time, or you can expire an item instantly using the following steps. Expired items are not removed from the database until the page group administrator performs a system purge of all expired items.
Note: You must be logged on as a page owner or an authorized user with the appropriate page or item-level privileges.
Navigate to the page that includes the item.
Note: If you do not see the page that you want to work with, you may not have the appropriate page access privileges. See your page group administrator to gain access.
Switch to Edit mode.
Locate the item that you want to expire and click 
beside the item.
Click Expire.
Changing an item's expiration period
What is an item?
What are item types?
What is an attribute?
Granting access privileges to your page
Granting access privileges to your item
Performing a system purge