To change your username and password, follow these steps:
- Go to the home screen and press your profile picture in the upper left corner to open your profile.
- Once in your profile, press the gear icon in the upper right corner to open your settings.
- Once in settings, press your current username to open your account settings.
- Once in your account settings, you can change your username and password (along with your profile settings, email address, and privacy settings).