As you can see, using our previous textures gives an accurate detail to the normal map. For many parts I used this Nvidia plugin settings
After doing a similar process with other parts of the model and using overlap layers as I have told, here are the initial and last normal map.
As I told before, exporting maps from our high resolution model will be useful for creating a base for our skin dark and light parts. You can export several diffuse maps using render to texture and changing lights in the scene and materials to your character. For example, apply a white matte material to your character, put a skylight in the scene, render to diffuse and use this map for a dirt map in Photoshop... you can see find a great tutorial about this in Pior Oberson's web page: http://www.pioroberson.com/tuts/tut_texturing_tricks.htm
(Notice he used a different technique for creating texture maps).
Showing up the Model
Once the model is finished, we need to show it up. So the ideal thing would be creating an illumination environment similar to games. For my final image I simply used a standard material putting the color map into the diffuse slot, the specular map into the specular color and specular level slots and the normal map in the bump slot as shown in the next image.
In that scene I also added one spot light and four omnis to illuminate the model from all views (since I wanted a 360 degree animation), each one with different colors. I used a orange for a hot illumination, a yellow for sun-like illumination and some blue and white colors for general ambient.
I also added a 30% of auto-illumination in the material.
Well, I hope this tutorial has been useful to you, and don't hesitate to drop me an e-mail if you have any comments or questions!
If you create a model following my tutorial, please let me see!! ;)