Problem

You want to be able to go through a scenario step by step when you are testing with a browser as sometimes can be very fast.

Solution

By following the suggestion here you would only need to add the following to your features/support/hooks.rb file

AfterStep('@pause') do
  print "Press Return to continue ..."
  STDIN.getc
end

and then you should be able to use it in your scenario by adding the @pause tag.
Then you would have to press continue in your terminal to go step by step