Cocoapods的新特性，在安装后仍然会出现错误

Question

这是我第一次这样做，但在遵循可可豆荚的在线说明后，我似乎无法在安装后使用它。有人能帮帮忙吗？

Ronalds-Air:~ ronaldm$ gem install cocoapods --user-install
/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/universal-darwin15/rbconfig.rb:213: warning: Insecure world writable dir /Users/ronaldm in PATH, mode 040707
Fetching: cocoapods-1.0.1.gem (100%)
WARNING:  You don't have /Users/ronaldm/.gem/ruby/2.0.0/bin in your PATH,
  gem executables will not run.
Successfully installed cocoapods-1.0.1
Parsing documentation for cocoapods-1.0.1
1 gem installed

然后我试着用这种方法

Ronalds-Air:~ ronaldm$ /Users/ronaldm/.gem/ruby/2.0.0/bin/pod install
/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/universal-darwin15/rbconfig.rb:213: warning: Insecure world writable dir /Users/ronaldm in PATH, mode 040707
[!] No `Podfile' found in the project directory.

我试过sudo，但没有帮助，任何帮助都是非常感谢的