3D modeling and design require applying a material to a vertex group. It uses specialist software to map textures and materials onto your 3D model. Select the vertex group to apply the material to. Open texture mapping software. Depending on the material and texture, this may be Photoshop or Substance Painter. Once you've opened the app, select a group of model vertices and choose a material. Adjust its features, including colors, hues, bumpiness, and reflectivity, based on the surface type.