Install composer and Yii2 on windows

Download and install wamp and composer from here if you have not installed php and composer yet

https://sourceforge.net/projects/wampserver/
https://getcomposer.org/Composer-Setup.exe

Open powershell in admin and run the following command:

> [cd to your own directory where you like to do development]
> composer global require "fxp/composer-asset-plugin:~1.1.1"
> composer create-project --prefer-dist yiisoft/yii2-app-basic myappname

The "myappname" is the directory to which yii2 will be installed