How to test a WordPress theme without a plugin

Recently I updated my blog to WordPress version 3.4.1, back before the whole 3.4 was out I remember being able to go to Appearance -> Themes and open the preview theme link in a new tab which would give me a full working version of my new site theme without having to use a plugin like Theme Preview, which unfortunately hasn’t been updated in a while nor does it work past version 3.4.

I am always making new adjustments to my current website and used to love previewing the changes before making them live, however after this update the new Live Preview link in 3.4 doesn’t work or do what I need it to do, I am not sure if this is a bug or it is not compatible with all themes or what is going on here but I thought I would share this simple way to fully preview your new theme without having to make it live especially handy for me as I am working on my new responsive layout.

Simply change the below link to your details and away you go. I might just add that obviously you have to be logged in to the admin for the link to work.

http://YOURDOMAINNAME/?preview=1&template=THEMENAME&stylesheet=THEMENAME