Here is a quick description of the technique (apologies, I did not see the replies!):
- Acquire a runway map; for example http://flightaware.com/resources/airport/KBOS/APD/AIRPORT+DIAGRAM
This airport diagram might be all you need and you can avoid any further work.
But if you like to have the satellite overlay view...
- Using Google Earth, zoom in to the airport (Type "Boston, MA" in the Fly To window at the top left for example)
- For each airport feature that you want to add, you can add either a placemark or a line directly in Google Earth. The icons at the top of the Google Earth window have the drawing tools that you need. Try marking a runway for example by clicking on the "Add Polygon" icon, then clicking on one end of the runway, then the other end. You can change the drawing properties for a line; click on the "Style, Color" tab that comes up in the dialog and choose a line color and a width of 8.0 or so. I just did a free hand drawing of each line.
The user interface is not the most friendly; have a look at http://earth.google.com/intl/en/userguide/v5/ug_drawing.html
for more info.