New to Google SketchUp? Take a look at this instructional video and learn how to draw shapes in Google Sketchup. There are four fundamental rules to drawing edges.
The first is that you must draw a closed loop of edges to create a surface, but your loop of edges must be coplanar. The second rule is to watch the axis directions and use inferring to line up the edges. Rule three is to learn and use the different inference points. These points are show in green dots. The final rule is to always draw to and from existing edges, or in other words, don't draw new edges over existing edges.
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