Scout Manager supports multiple options to login.
To use your Google Account you'll need to have your @gmail.com account setup as your email address. At login select Sign in with Google and you'll be walked through the process of associating your Google Account to your Scout Manager Account. The process is quick and consists of the following steps:
When finished you'll be logged into Scout Manager. When you visit Scout Manager again in the future and you're already logged into Google you'll automatically be logged into Scout Manager.
To use your Facebook Account you'll need to have the same email address in Scout Manager. At login select Continue with Facebook and you'll be presented with a Facebook Login page. Once authenticated you'll be logged in and forwarded to Scout Manager.
If you don't want to use Google or Facebook credentials or you don't have an account with them then Scout Manager can manage your username and password. At login just type in your credentials and click Sign in.