With roscore running, start rqt_rviz (note that rviz is still valid in ROS Kinetic) with:
$ rosrun rqt_rviz rqt_rviz
We will see the graphical interface of the following screenshot, which has a simple layout:
On the left-hand side, we have the Displays panel, in which we have a tree list of the different elements in the world, which appears in the middle. In this case, we have certain elements already loaded. This layout is saved in the config/example9.rviz file, which can be loaded in the File | Open Config menu.
Below the Displays area is the Add button, which allows you to add more elements ...
