How to update htaccess after changing page URL?
 

So I have changed several page URLs in sitebuilder to make the page link shorter, however now if a visitor lands on the site with the original URL they are getting 404. So how do I fix this in htaccess?
Example:
Original Link: http://www.kingcruisers.com/forum/roll-calls/cruise-lines-a-l-roll-calls/carnival-roll-calls/carnival-freedom-roll-calls
New Link: http://www.kingcruisers.com/carnival-freedom-roll-calls

Thanks!