Install Composer into XAMPP 1.8.3 on Windows 7 + Laravel and Yii2

How to Install Composer into XAMPP 1.8.3 on Windows 7.
Also how to use Composer to create a basic Laravel and Yii2 project.

Web sites used in video: http://www.palmbeachstate.edu/faculty/venturap/xampp-composer.html.

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