To be able to show one's dogs, they must be Kennel Club registered. The Breed Standard must be studied, and it is essential that faults can be seen in one's own dogs. The Breed Standard is a Kennel Club blue print for what each dog should look like. The more serious the fault, the less likely they will have much success in the show ring. Showing can be taken lightly for a bit of fun, or expensive, time consuming and very serious.
All dogs are groomed prior to showing, and can play a large part in how well they will do. Each breed must be groomed or clipped in a certain way for showing, and some breeds must have a full coat that is not clipped/cut, and so look natural, other breeds must be clipped/cut to a certain style. Terriers and some other breeds are only handstripped.
For example, if I am to show my Shih tzu, they would need to have a full coat down to the floor, as it would be naturally, only under their feet will be trimmed, the hair on top of their head is tied up . My Leonbergers will be bathed, brushed and feet lighlty trimmed.
There are different types of Shows, Companion, Limit, Open, and Championship.You must research and decide which one is right for you.
There are lots of show's you can enter around the country, but to show in Crufts, you must have qualified.