按照 文档 操作，

1.先安装composer，然后下载laravel安装包：
composer global require "laravel/installer=~1.1"
命令执行成功。

2.将目录~/.composer/vendor/bin添加到系统环境变量中。
3.运行laravel new test命令创建laravel项目，报错如下：

 E:\>laravel new test
Crafting application...
Composer could not find the config file: C:\Users\yanwushu\vendor\bin
To initialize a project, please create a composer.json file as described in the
https://getcomposer.org/ "Getting Started" section
Application ready! Build something amazing.

个人对composer和laravel都没有比较清晰的理解，请熟悉的同志给予指点。