The best way to scale a 3D model along a specific axis is to use your 3D software’s axis-specific scaling tools—select the model, choose the X/Y/Z axis handle (like in Blender, Maya, or SketchUp), and drag or enter a numerical value.
This keeps proportions consistent in other axes, avoiding unintended distortion. Most tools use color-coded handles (red=X, green=Y, blue=Z) to lock scaling to one axis, with numerical inputs for precision.
For beginners, try Blender: open your model, press “S” for Scale, hover over an axis handle to highlight it, then drag or type a number (e.g., 2 to double size)—it’s simple to practice.