Click on login button on top of https://k2s.cc page and then click 'I forgot my password' on the login page. Then enter you account email address. You will receive e-mail instructions on how to reset the password.
If you are logged in, go to your profile and click the "Change Password" button
If you do not receive an email with a link to reset your password, check the SPAM folder of your email. We also recommend checking the Trash folder to make sure you haven't accidentally deleted an email.