You can view the detailed instruction on how to change the account password in the My Profile section.
To change a password in the account go to the Account Settings > My Profile section or click in the upper right corner on the user’s name.
On the “My Profile” page select the “Security” tab and choose the “Change Password” block. To change the password fill in the following fields:
New Password (must be at least 8 characters long, have a mixture of uppercase and lowercase letters (a-z), contain at least one number (0-9), and include at least one special character (!@#$%^&*))
Confirmation Password (retype the password you entered in “New Password” field)
Click the “Save” button to complete.