Help with modeling to UV mapping I'm new to blender. I wonder to know how to model things that can successfully create its UV Mapping. Are there any tips? 

As you can see, I model a coat but it doesn't work with UV mapping. If anyone knows what's happening on my coat, please let me know. Thank you!
   


I got the UV mapping which looks not good. I wonder are there any tips to mark seam? 


I used smart UV projects and I got the one looks better. But there are a lot of islands on UV editor, is that ok?
I think the reason you don't see your UV map, is blender doesn't preview image textures unless you change the view mode. 

If you look at your 3D window on the right... at the bottom toolbar... next to the words "edit mode" is a little box with a white ball. This is where you change the view mode. Right now it's in "solid" mode, so no textures, just solid mesh shape. 

Click it and choose "Material" mode. Then you'll see your image textures applied to the mesh. You could also go into rendered view by pressing shift+Z, and you can exit rendered mode with shift+Z again. Rendered view will also show your image textures. But it might not show anything if you haven't added lights and positioned your camera yet. So first try material view.