I like to navigate through Rubymine using only keyboard shortcuts if I can. One of the most useful techniques I have found is mapping a keyboard shortcut to enable you to run the test that your cursor is on. This way you can navigate up and down tests using ctl + up or down and then run the test your interested in with your key stroke. Even though I am on a Mac I prefer running a test to be mapped to control + t. The default configuration for this is command + alt + F8. The keymap configuration is under the label Run context configuration, which is under the All Actions -> Other section in the Keymap configuration menu.
The other shortcut that goes well with this one is Go To Test. I can put my cursor on a class name and press alt+shift+t and I can view the tests implementation for this class. Then I can use the short cut I created ctrl + t to run a test I am interested in.
Great work Rubymine team.