Mark Seam
Select each 3D object to create customized UV. With tab key enter the editing mode. With the Number 2 key the borders are selected. Unwrap the 3D object accordingly and select edges with the shift key pressed. Proceed to Control + E keys to Mark seam. Having selected our 3D object with the A key in edit mode use the U key to unwrap. In the UV editor (Shift + F10) we can see the diagram of the slices of our object. Make sure faces of the object don't overlap.
Materials
To create materials on the selected 3D object pick from the material properties tab the ones you need for your object. Then select once again the object under edit mode (Tab key), proceed to select each face and assign the material accordingly.
UV Smarth Project
Select the 3D object, press the Control + A keys and then click on All Transforms. Choose the tabs Object/Set Origin/Origin To Geometry tab in that order. Under edit mode, select all faces (A key) and then use the U key to select Smart UV Project. Set up the properties to secure faces don't overlap. In the UV editor (shift + F10), arrange faces based on the model textures (i.e use our tutorial video to guide you through the process). Be sure that all faces on the selected 3D object should be inside the UV box.
Export UV Layout
In the UV tab select UV/Export UV layout. Then set up the size to 1024X1024 and proceed to export the UV layout.
Texturing
The UV map must be exported on JPEG/PNG file at a maximum resolution of 2048. Proceed to import this file to an editor imaging program like Photoshop. Perform the required adjustments on the UV Map accordingly. Make sure to make a seamless texture when using tiles or repetitive patterns.
Lighting
To add the lighting to the model, we need a 3D light source (i.e, lamp, lightbulb). To create a light we make the key combination shift + A/Light/Spotlight. With the G key and on the X, Y, Z axes, proceed to move the light. Within the rendering tab, the light can be seen, proceed to the properties option, and set up the light condition based on the space type.
Transformations
Once you are done with 3D object, please set up the scale to 1. Proceed to select All transforms with Control + A keys. Center the origin in the Object/Set Origin/Origin To Geometry tab.
Create Glb File
Once the 3D object is properly adjusted with our prior guidelines, select the 3D objects and proceed to export them using a native blender GLTF 2.0 exporter. Use the glb extension file to save your object. Consider several options under the rollout tab.