What your asking would fill a book for answers. Look around at lures, their functions, and hey go to the store and buy a cheap chinese lure, take it home and cut it up....Your not going to be a rocket lure genius right away you got alot of learning to do alot of which I don't believe in handing people on a silver platter. I believe in trial by fire on the seat of your pants.
Make a lure, put some with lead in it, some without then take them out fishing...learn what makes them tick and you'll enjoy it that much more when you make one and catch a fish on it. You will quickly learn what is a dud and whats not.