The Art of Logo. Finishes include various decorations such as surface textures, drop shadows, highlights, gradients, transparency, etc.
People generally believe that cool finishes is what makes their graphics professional.
Far from that. Finishes may give, as the word implies, a finished appearance, but no amount of drop shadows will improve a logo which is designed poorly with regard to its shape or color. Strictly speaking, finishes do not represent a separate media, so in applying them you can refer to all the principles I've tried to outline above. Speaking of tools, the stage of applying finishes is where you quit your vector drawing package and export your creation into Photoshop or other painting program. This looks great and helps to integrate text and graphic into one tight bunch.