Hope you're ready for opening a can of worms. UV mapping is difficult area to jump in to.
To get you started, select your poly object, then select "edit polygons"->texture->automatic...
from your panels menu, select panel, saved layouts, persp/UV editor in order to see your scene and the uv editor side by side.

From there it gets much more difficult, but start there, play with selecting uvs, edges, faces between the two panels to see how they interact with eachother.