UV textures not applying to skin modifier Please excuse the fact that I am a beginner in Blender. There may be something obvious that I am missing.

An exercise I tried recently:

1) Open a new blender default file. 
2) Collapse all of the vertices of the cube to the centre. 
3) Add the skin modifier to the object. 
4) Extrude the vertex. 
5) Open UV editing, and try to unwrap the mesh to apply texture.

I observed that I was unable to apply a texture to the mesh. I suspect that this is because of the fact that blender is trying to apply texture to the underlying mesh, rather to the mesh generated around the edges and vertices by the skin modifier. Would there be a way to UV map the skin generated mesh, and if so, what would that method be?

Thank you in advance.

Post Script:
if you have any criticism of this question, I would appreciate being told what it is, rather than just receiving a down-vote. Also, for this particular question, I spent several hours googling to try and find a solution, however, the Internet tends to siphon one into the most popular results, rather than the most helpful, but obscure, so it is entirely possible that I have simply been barking up the wrong tree.
You must Apply the skin modifier to be able to unwrap the mesh. Once applied, you will get acces to the generated mesh. Just press the "Apply" button in the modifier parameters.