Step:1)Open the facebook which make your account.
Step:2)After open the facebook you will see the Home page of facebook.
Step:3)Open the setting in facebook.
Step:4)After open the setting here setting is general.
Step:5)You open the down setting which is (Blocking) in setting.
Step:6)You will seeing a all block setting (Block User,Block App etc).
Step:7)Now you click the Block User.
Step:8)Enter the name and email which want to block you in block User.
Step:9)After enter the name or email your friend will block.