The beauty of a mail-order business is that you can test a product to see if it will work, without putting too much expense into it. If at first you don’t succeed, try, try again. Do not give up on your mail-order venture just because something didn’t work out the first time.
Keep learning and keep trying. Be ready to learn from your mistakes as well as your accomplishments. While you are learning, document your findings in your journal. Who know, it might become a profitable tips booklet later down the road.