Setup by adding class

You can activate the option to open the left sidebar on click event by adding this class (am-left-sidebar--click) to the left sidebar element (am-left-sidebar) element, this way your main structure should be like this:

<html lang="en">
  <body>
    <div class="am-wrapper">
      <nav class="navbar navbar-default navbar-fixed-top am-top-header">
        <!-- Top bar without sidebar toggle buttons -->
      </nav>
      <div class="am-left-sidebar am-left-sidebar--click">
        <!-- Left sidebar -->
      </div>
      <div class="am-content">
        <!-- Main content -->
      </div>
      <div class="am-right-sidebar">
        <!-- Right sidebar -->
      </div>
    </div> 
  </body>
</html>
Setup by App option

You can also activate the option to open the left sidebar on click event using the main App option openLeftSidebarOnClick(Default: false) in your App.init method like this:

<script type="text/javascript">
  $(document).ready(function(){
    //initialize the javascript
    App.init({
      openLeftSidebarOnClick: true
    });
  });
</script>