button_to with GET method option in Rails

Buttons aren't supposed to be sending GET requests.

You should use a link_to instead. If you want it to look like a button, apply some CSS. Here's a good article: http://coding.smashingmagazine.com/2009/11/18/designing-css-buttons-techniques-and-resources/

Just use method: and :get

button_to "New User", new_user_path, method: :get