There are a few things you can do to help your illustrations look more realistic and 3-D. One is to use more perspective, or to change the way light reflects off objects. Another is to use more shading and shadows. And finally, you can use more color in your illustrations. To get started, here are a few tips:

  1. Use perspective in your illustrations to make them look larger or smaller than they actually are. This will give them a 3-D effect.
  2. Use shading and shadows to create depth in your illustrations. This will make them look like they’re made of different materials or have different textures.
  3. Use more color in your illustrations to give them a warmer or cooler tone. This will make them look like they’re made of different colors or have different hues inside and outside of the illustration itself.