Answer :
Well from personal experience I would have asked what kind of sculpture they would want and if it has to deal with people go to heavily populated cities and just look around and sooner or later you will eventually you will find a few people that will take your breath away and just keep that thought in your head then just go for it, If it has to deal with nature I would go out side with a camera and just explore abit and take pictures of animals then when you think you found it do the same thing you would do for a person sculpture, and just motivate yourself.