For security reason is recommendable to change the default ssh port (22) in order to do that you need to follow.
- Login to your server using your favorite ssh client like putty
- With your favorite editor open /etc/ssh/sshd_config (ex. # nano /etc/ssh/sshd_config)
- Look for #Port 22, if its commented, then uncomment it and change 22 for whatever you want, please be careful and use and not used port.
- Save the changes, and exit your editor.
- Restart your sshd service and thats all.