When people think about creating vector graphics, they tend to think of CorelDraw or Abode Illustrator. But while it is true that these programs are specifically designed to create vector graphics and have a wide range of tools for accomplishing that task, it is also possible to use Photoshop's tools to create good quality vector graphics.
Instructions
1. Open Photoshop. Select "File" and click "Open." Search for the image you want to use for you reference and open it.
2. Go to the "Layer" panel, right-click on the layer and select "Duplicate." Then go to the "Opacity" slider and drop the opacity by half. Then click on the "Background" layer.
3. Go to the toolbar a pick the "Pen" tool (make sure it is set to "Shape Layers"). Use the tool to draw the outer shape of the object in the image. If you need to adjust any of the points, select the "Convert Point" tool and move them around.
4. Change the "Foreground" color. Then go to the "Layers" panel and click on the "New Layer" icon. Now use the "Pen" tool to draw in some of the inner shapes. If you were doing a car, you might now draw in the shape of the windows.
5. Keep creating new sections, subsections and sub-subsections. With each new level of detail, change the color you are using. You can create a line around the shapes by going to "Layer" and clicking Rasterize Layer. Then go to "Edit" and click "Stroke." Set the width and color to what you want and click "OK."