The majority of the piggies in today's world are not considered showable, according to the American Rabbit Breeders Association's Standard of Perfection, which is what we go by for showing in the United States, unless you are showing at an OCC (Ontario Cavy Club) show or a fitting and showing 4H show.
For the US purposes, however, we go by the ARBA Standard of Perfection. You will need to get a copy of this if you do want to show, so you can learn the ins and outs of what is acceptable and desired in a show piggy. You can order one online from Woody's Wabbits Supplies in Astoria, Oregon.
Due to copyright laws, I cannot quote the Standard to you. I can however, give a brief description of what each breed is, as well as what the judge should be looking for in the breed.
To find out what kind of pig you have, please see my article on What Kind of Piggy Do I Have? and we'll start from there. Abysinnians are a short haired pig with 8-12 rosettes on their body. The judge mostly looks for a healthy animal with evenly spaced rosettes on the body, forming very distinctive ridges. If the rosettes are very open centered, this will lead to a flattened rosette and there won't be much of a ridge around that rosette. The ridges are created where the hairs from two neighboring rosettes meet. Abys are traditionally longer in the nose than other breeds, as well as slightly more high strung and nippier than other breeds. The satin Aby is judged the same, only they also have points awarded to them on the sheen (shine) of their coat. While markings, colour and body style are all important, the bulk of the points lie in the placement of the rosettes (they should make a band around the top of the pig at the shoulder, at the midsection and over the rump) as well as line up straight from the front of the animal to the rear of the animal. Other things to look out for within the rosettes is guttering (an elongated center, more like a slash for a center) or doubled rosettes which are two rosettes placed extremely close to each other, creating a second whorl.