To increase security for your account, you should regularly change your network account password.
Change your network password by going to the following web page: https://reset.cabrillo.edu/
See also: What makes a strong password
Changing the password locally on the machine:
If you are using a Mac with OS 10.6 or earlier, or any Macbook Air with any OS, after changing your password with reset.cabrillo.edu, you should also change the password in the local settings on your computer.
This step only applies to OS 10.6 or earlier and Macbook Airs. If you are using Lion (10.7) or Mountain Lion (10.8) - it will break the login process.
If this step applies to you, after using https://reset.cabrillo.edu/ to change your password, then review these instructions:
Apple OSX Support - "Change or reset the password of an OS X user account"