While Unity has a very well integrated Lightmapping system, it might make sense if you do the baking in dedicated rendering software, such as to use advanced Global Illumination. Most current DCC applications support light baking, including CINEMA 4D and 3ds Max.
When you use, for example CINEMA 4D, this is available for texture/light baking. This can be achieved by following these steps:
When a scene is set up, select the object and choose Bake Object from the Objects menu inside the Objects browser.
In the dialog, activate Ambient Occlusion and Illuminate and choose an output folder to save the textures to.
When you press bake, CINEMA 4D will render the lighting and materials onto the object and create a new mesh, with optimized UV mapping. The original mesh is kept hidden if you ever wanted to make any changes.
When the baking is done, check that it works, by disabling GI and lights and call render. In a fraction of a second, the model will be re-rendered.
When you load...
