Obtaining Authentication Credentials from Google's new style API Console
In a new browser window open Google's Developer API console.
At the first page "dashboard", click on [CREATE PROJECT].
Provide a Product name and some sort of unique Project ID.
Open the menu [APIs & Auth] . . .
. . . and its submenu [Consent Screen].
At a minimum you must provide [EMAIL ADDRESS] and [PRODUCT NAME]. This page is your "calling card", which Google passes on to third parties. Make it nice. Confusing information here can increase your rejection rate.
Next open the [APIs & Auth] submenu [Credentials].
Click on [Create new Client ID]
Choose [Installed application] and [Other] radio buttons, then click the [Create Client ID] button.
Click the button [Download JSON] and save to your project directory.
