How to add Location to share Security

Share Hard drive.
Right click on drive to share, click share, click Security tab, click on edit, click on add, click on Locations.
How do i add a network Location in this section please.

Ummm, how do you share a location that is a network location in the first place? By the definition of a network location it is being shared to you, right?

I want to share my desktop hard drive on my network at home, but i dont want every body on the network to have the same controle level.
My laptop must have full controle and the rest not.