1)  Go into System Preferences→Sharing and enable Remote Login:

2)  Verify SSH server is working on the mac using Terminal.

Type the command:  ssh  username@localhost

You will then be asked to verify a server key.  Type yes , hit return and then type in your password.

You can then test commands as below:

3) Connect to the Mac, remotely.

  You can either connect via Terminal from another Mac, or if connecting via a Windows machine, I would recommend using Putty:


Note: The first time you log in remotely, you may be prompted aboout the server key again.  Just click on yes.