By accessing your Account Settings under Basic Info, you have the option to change your password underneath where you would put in your email address. Once you click on "Change Password" it will send a password reset request to your email address that you have associated with the account.
The email should look something like this:
There is an instance in which you can run into an issue when trying to change your password where you will first need to authorize your logged in location. If you find yourself unable to do either of these consistently, please open a ticket: http://support.raptr.com/support/tickets/new