Step 1: Get Reader SDK credentials
Open the Square Application Dashboard. You will be prompted to login or create a new account.
Create a new Square application and call it "Reader SDK Quick Start".
Click on the "Reader SDK Quick Start" app to bring up your Square application settings pages.
Open the Reader SDK page and click "Request Credentials" to generate your Reader SDK repository password.
Keep your Reader SDK settings page open. You will need the Application ID and Repository password to configure the Reader SDK sample app in the next step. And you will use the "Generate Mobile Auth Code" button to authorize the sample app in later steps.