angularjs - Angular ui-router : Passing params between states

I'm trying to pass a message from state1 to state2 in ui-router.

looked up most of the question on here about this topic but unfortunately can't make sense of it.

This is my main code and $stateProvider :

myApp.config(function($stateProvider, $urlRouterProvider) {
  //
  // For any unmatched url, redirect to /state1
  $urlRouterProvider.otherwise("/state1");
  //
  // Now set up the states
  $stateProvider
    .state('state1', {
      url: "/state1",
      templateUrl: "state1.html"
    })
        .state('state2', {
      url: "/state2",
      templateUrl: "state2.html"
    })

});

Here is a Plunker of what i created to test this out.

What should i do to make it work? Thanks