NICHQ hosts several independent CoLab sites, each with its own user accounts and content. When you visit one of these sites, you'll be presented with the login form (1):
If you have an account already, you can enter your email address (2) and password (3). Then click the blue "Log in" button to gain access. If you've forgotten your password, click the "Reset your password" link at the top of the form, where you will be taken to a separate form:
Enter your email address (5) and click the blue "Submit" button to receive a unique link that can only be used once to reset your password. Clicking that link will bring you back to the site with a notice that you are using a one-time login link and will need to set your password once you click the blue "Log in" button (6):