Tell me about rules of dress designing.

Im sorry I'm not totally expert in dress designing but i can  able to do as a dress sewer...but I have some idea in dress designing... Dress designing it base if u are a fashion designer .so have ur own idea to create any dress design without copying by any catalogues. That a very unique talents cause u do any style of dress by ur own creations it means smart minded.....but if you a sewer only you follow what is the customer requests. On every stlye of dress that she like.it means follow the design that she chossen..so i think that the rules we must follow..