And how does it work if i enter? (what are the rules and what are the judges looking for) etc
Thanks.

It's all about having a well trained dog and being a responsible owner. All the info you need can be fund on this page:
http://www.thekennelclub.org.uk/dogtraining You will for instance find details of what you and your dog have to pass for each of the different tests. If you're thinking about taking the test at a dog show, it's the Bronze you will be able to do there, not the higher tests normally. To be able to enter the GC CLASSES at Crufts your dog must have passed at least bronze.

Thanks for the info.

Just to add, when you have your GC Bronze or higher and enter the class at Crufts it is judged on confirmation like any other class.  You are just left safe in the knowledge that your dog has brains and manners as well as beauty!