How do you run a ssh server on Mac OS X?
Go to System Preferences -> Sharing, enable Remote Login.
In System Preferences under Sharing, there is an option for Remote Login.
This will run sshd at startup (through launchd) and enable SSH access with standard options. To tweak the sshd options, edit
/etc/sshd_config (you'll need to do this in a sudo shell or via
sudo vi /etc/sshd_config).