You have two options: 

1. You can choose the "Forgot Password?" link where you sign in

2. After you have signed in, please click on your name in the upper right. If you don’t see a green box with a check next to your email address, then follow the instructions to verify your email address. Only registered learners with a verified email address can change their password on their own

If your email address is already verified, then click on “Account Settings”, choose “Change Password” and follow the instructions.