You can change your login password by navigating to your name in the bottom left corner>Profile:
Find the Change Password link. After clicking, you will need to enter your current password followed by choosing your new password.
If you need to change your password but can’t recall your current password, Go to the login screen and click Sign in with email:
Then click: Having trouble logging in?
You will need to enter your account email and a reset link will be emailed to you.