Bridges, especially elevated bridges, differ from railway models as they are three-dimensional rather than flat. Therefore, to create an interlocking sense of layers, it primarily relies on color depth, contour lines, and shapes. It is specifically categorized into three-dimensional and flat production methods. The flat production method is usually used when bridges are considered accessories. To showcase the bridge itself, the three-dimensional production method is generally employed, as it clearly displays the size and height of the bridge. The specific methods are as follows:

1. Hierarchical Representation: Employ contour lines to display the height, dimensions, and levels of the bridge. During painting, the color transitions from light to dark from top to bottom, and shadows are created for a more realistic visual effect.

2. Width and Narrowness Representation: During the construction of bridges, visual errors can be utilized to differentiate widths, rather than strictly adhering to proportional reduction. Instead, certain widths can be intentionally enlarged to create a distinguishable difference in width visually.

3. Perspective Representation: Since we typically view models from above, the greenery strips and guardrails on both sides of the bridge should be made taller to ensure they are not obscured.

4. Fixed Model: The completed model must be securely fixed to the base platform, allowing for piecemeal gluing. This ensures that each section is not overly long and that the joints are reinforced, ensuring stability of the model.