Automated Database Backups?

How would I go about making automated database backups every 24 hours?

Also, is it possible for the database backup to be deleted every three or so days so I only have a maximum of say 3 backups at once (to save disk space).

I am opening a website that allows admins to delete / edit content and if one of them goes awol or looses their password I would like the damage to be minimal.

It's cool, I figured it out.