I’m very new to Blender, so please be patient with me :o I’m trying to do a Renault 8 rim, something like this : 
I’ve created all the wheel, excepting the tire, and now I want to make that cap shiny, as in the picture. So I’ve selected the cap’s faces and I’ve created a new material, but the hole wheel gets this shiny material, and I don’t want that.
Help me, please!
P.S. Also, could somebody correct my tenses? The english language is still a mystery to me 
" I’ve created all the wheel, excepting the tire" should be “I’ve created the whole wheel, except the tire.” - “All the wheel” isn’t right unless it’s “All the Wheels” and drop the ing off excepting.
As far as your problem, this is the most common question of all beginners I think, it’s easy to fix though.
Go into your edit buttons and you’ll see a box that says 1 Mat 1. This means one material index out of 1. If you want more than one material on the same mesh, you need two or more material indexes. So hit New and make it 2 mat 2, then select the faces you want different from the rest of the wheel and hit Assign. Now go into your materials, and you’ll see the number 2 next to the box where it says MA:Material. This means that MA:Material is a material that is assigned to 2 different material indexes, 1 Mat 2 and 2 Mat 2. So click on the number 2 and make it a single user, this gives 2 Mat 2 it’s own personal material.
Switch between the two materials by clicking on the 2 Mat 2 there in materials.
Thank you very much, both for checking my spelling and helping me with the wheel 
All is now very clear to me!
Hi, me again!
Still a noob, I have restarted learning blender 3 weeks ago, and started from scratch the Renault 8. I have modelled the rim, again, and here is my question:
What should I do have a reflection on that little cap? At this moment the raymirror is activated, so when I render the wheel, the cap is taking the background’s color.
I want , that instead of a plain color, to have a photo reflected.
I added a plane in front of the wheel, set a photo , with uvmap, I rotated the plane so that the texture to be towards the rim, and rendered it, but I’m seeing only the plane reflected, without the texture on it. I hope it’s clear… It’s good, my approach?
AstroStef,
In the material panel, make sure to toggle TexFace on.
Best of Luck!
Thanks! And what should I so the texture be applied on both faces of the plane? Is there another magic button?
Up! This is the wire, after 2 weeks of work; I know I’m offtopic, but I need an answer for the previous question
In blender, there’s always a magic button. To make UVs double-sided, select the object that has the texture, hit “F” to go into UV face mode, and select one face with RMB. Then down in the buttons window (f9 tab), click “twoside” or something similar. Then select all faces, and click “copy draw mode”.
The modeling looks great, by the way.