The Tips in detail

 "How to use multiple textures on complex objects, like ie. a head?"

It is possible to use multiple materials with different UVW co-ordinates and alpha channels. One way to map for this and how to do this is like this:

What you need to do is apply a grid or checkered map to the mesh with planar mapping. Make the texture viewable in the the viewport. Turn on texture correction in the perspective viewport so the image isn't distorted.

Try and visually break the head down into seperate planes, like front, side top, back. Then, basically, position the planar mapping gizmo to project on those planes. Each time look for the stretches on the texture that the mapping causes. i.e. The front of the face will look good, but the sides will begin to stretch... you get the idea.

Where the texture is pretty uniform, select those faces and assign them a material ID. You basically do this for all sides of the mesh, like the front of the face, the sides, the top and back. The alpha channels go along the areas of distortion to blend the the seperate material ID's.

But to lead back to the original question, to apply different mapping to one mesh, you have to apply an edit mesh, select the material ID in question, and apply UVW mapping to that selection of faces. But you can't go selecting the next material ID set of faces and applying mapping. You have to apply another edit mesh and repeat the process. Now that I think of it, it should conserve more memory to use Mesh Select as opposed to Edit Mesh. You can, however, (I believe, haven't done it yet) apply a second set of UVW mapping coordinates with the same Edit Mesh modifier by using the 2nd Mapping Channel. Then you apply a Multiple/Sub Object Material to the mesh with different textures and alpha maps for each material ID.

Check http://www.mastering3dgraphics.com free tutorials section for the Surfacing Secrets Tutorial in PDF format. It has a great description of mapping techniques for characters, but doesnt directly relate to any specific 3d app.

Hope it makes sense...I could have made some errors in my description, write back with any questions...

from: Brad Newman <bnewman@iastate.edu>

Have a look at "How do I get smooth textures?", too, for further info.