Anything goes Clare. My advice - be smart but comfortable. Treat the judge with some respect - which shows in your dress, and that way you'll start to earn respect too. I can't believe how some people go into the ring. It is the dog that's on show but if you feel good, that will encourage your dog to feel good too.
Watch your colours though and don't wear anything to flappy - ie very long full skirt or lightweight baggy trousers - they can put the judge off by pulling their eye away from the dog. If you're showing a black dog, don't wear black. Wear a colour that contrasts that way the outline of the dog can be better observed.
hth
