A simple fly through tour: Producing a tour is wonderfully simple, an example would be a flight to show the physical landscape in the Grand canyon as in the video above. Effective instructions on how to produce such a tour are here from Google.
Producing a Smooth Flight: To produce such a tour you can simply use the mouse controls but you will get a better quality flight if you use a 3DConnexion mouse. If you don't have one or another way of improving the quality of the tour is to produce placemarks which serve just as camera viewpoints and use them to record the tour. To do this:
- Fly to the first camera viewpoint you wish to capture for your tour.
- Create a new placemark, name it something like 'View 1' and click 'OK'
- In the places column right click the placemark and select 'Snapshot View'. This associates the current view with that placemark.
- Fly to a new position and repeat from step 
- Repeat for as many viewpoints as you wish to create
- Now untick the placemarks you've created in the places column.
- double click the text of the placemark in the places column and you will fly to the view but without seeing the actual placemark.
This isn't the most elegant way of recording a tour, writing the code directly would be better but many people don't have the skills for doing that in which case this is a sensible approach.