Question: Suppose I have my live site at `www.mywebsite.com`, tracked and managed via Google Webmaster Tools. Then I want to add to the project list a subdomain like `test.mywebsite.com` which I use for testing purposes. Of course that subdomain shouldn't be tracked or indexed by Google, but I would like to use "fetch as Google" feature on it to see how the crawler manages the pages. Can I set up such a test environment without being indexed by Google?

Answer: 
Google can't provide any information about your website if it's not indexed. 

In other words, you can use Google Webmaster Tools without your website being indexed, but it will be pretty much useless, since will not provide any data.
Google webmaster tools won't let you do that but you can test a website for seo checkup or other errors like search description missing,image alt missing etc with bing webmaster tools