Mac OS X has a built in ssh terminal application called terminal.app and it is located in the Utilities directory in the Applications folder. Once you launch terminal.app (Mac's SSH client) you will see output such as the following:
Last Login: Thurs Jun 17 14:17:43 on console
Welcome To Darwin!
Once you have launched the terminal app and see the prompt as above, type the following command:
ssh firstname.lastname@example.org (where xx.xx.xx.xx is your server's ip address)
You will press the enter key from here. Afterwards, you will get prompted for the user name's password. In this example, we are logging in as the root user. You will enter root's password, and your now logged into ssh console.