Locking a chest/door/furnace

I am going to teach you guys how to lock a chest/door/furnace using signs (Lockette)
!FIRST!
Get a sign and place it next to the designated items.
!SECOND!
Put on the first line of the sign saying,"[Private]" (no quotation marks)
!THIRD!
Put your name on the second line.
!FOURTH!
On the third and fourth lines you may put your friend's names

EX:
-------------------------
| [private] |
| your name |
| friend1 |
| friend2 |
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|