, According to Google's guide, lighting is like cutting and folding a paper. Think of this as origami. Fold the paper into any shape and then illuminate (light) it.
 According to above analogy, note how edges create shadows and where. Shadows give depth to 2D image.
 According to Google's outline, the color opacity is 54% on lit background. Inactive background will be 26% opacity-wise. On black background, opacity is 100% and inactive icon will have 30% opacity.
 Google's icon guideline further delineates other elements such as geometry, strokes, human iconography, etc.
Use grids and basic shapes: The basic shapes and grid let you focus on each element in the consecutive layers e.g. lighting, shading, color, geometry, etc.

,
Light carefully.
Observe the shadows.
Color according to their suggestions.
Dig into any other details.
{"src": "wikihow-all_validation", "title": "How to Create Interesting App Icons2"}