To work in Spline, you need to know, remember, and understand the following things:
3d is a 3-dimensional graphic, which means you work with 3 dimensions: x-axis (left-right), y-axis (up-down), and z-axis (front-back).
To achieve a good-looking or even a realistic 3d, you should never forget about 3 essential aspects:
Objects should reflect the light. By processing light and shadows, we understand the shape and surface of an object.
Context provides us with more information about the object based on its relations with its environment.
Little details are the things that complete the picture. In natural life, objects are imperfect.