Suppose I make a cube whenever I texture it only the top is textured and all the other sides look messed up. How do I textures all of the faces?
UV mapping is the answer!
I hope this link will be of help --> http://wiki.blender.org/index.php/Doc:Manual/Textures/UV/Unwrapping_a_Mesh
You have to change from flat to cube in the map input tab
