When you log on to your account, you can go to your profile page, and in on the top right hand corner, there should be an "account settings" or settings option you can click on, and a drop down menu...
first you go to the place were it writes log out above it, it writes privacy settings when you go in that it will tell you the rest
Well all you do is you go on Settings and then you click on profile settings, It is as Simple as that!
well right click then press deleet.
Go on their homepage then the lower part of the picture and says block friend (or delete friend) MUST WORK