names of objects, materials

I have been making clothes for my animated man which has armature (not sure if that is relevant). I made the clothes by the following method. I selected vertices in edit mode,duplicated them, scaled them up, separated them with P, put the object eg hat onto another layer with M. I have been wanting to apply materials (mostly colour) to each object. In the links and materials section, I tried changing the name of each object OB and giving a name to the selected colour ME. However, it changes the name for all objects. I have so far made a hat, coat, shirt and body. What am I doing wrong or is there a step I have missed along the way. Also one of the eyeballs appears to be linked to the hat, because when I change the colour of one it changes the other. However, they appear to be separate objects when selected and are on separate layers.
Thanks for any help

You need to understand about materials.
Different objects can share the same material.
Understanding how blender handles data may be useful to understand
By the way this should be in the Support forums, not News&Discussion

thanks, I will have a look. Sorry this is in the wrong spot. WD