When you unfriend someone on Facebook, the only information that you can see is the information that this friend allows all public members to see. You may not be able to see his wall, photos, status updates, personal information or friends list if you unfriend him. You are not prevented from friending the same person again, although your friend does need to accept the request in order to reestablish the Facebook friendship.
Open an Internet browser and log in to your Facebook account.
Type your friend's name in the search box at the top of the page, and press "Enter."
Click the friend's profile, and click "Add Friend." You'll receive an email when your friend request is accepted, if you accept emails from Facebook. You may want to click "Message" and send a personal message to the person you're adding to explain the second "friend" request.