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The wiry-coated terriers would need periodic plucking or stripping, likely about two or three times a year, to keep the coat free from snags and hard in texture. When left untrimmed, the hair grows long and thick, causing the dog to be quite uncomfortable. Besides, he looks kind of like a stray rather than a stylish, well-tended pet.
Using a stripping knife or dull penknife held between thumb and forefinger, you will be able to pluck out loosening hairs as the terrier coat is cast. You may do better, however, to take a couple of lessons in the art or to allow a professional pet groomer to do the job. If you want to handle the coat yourself, you can buy trimming guides and charts having excellent directions for every breed at your pet-supply store. You can also purchase the correct tools to do the job the right way.
Certain breeds—Cocker Spaniels, Poodles, and Bichons Frises especially—involve clipping and scissoring expertise, and an amateur might have a difficult time trying to make his dog look right. There are a number of hairdos for Poodles—the Continental, the English Saddle, the Dutch, the Sweetheart, for instance—each one finishing up the dog having a radically different outline. It’s a big job, to be sure; the Poodle has a wealth of coat which should be taken off in some places, left on in others, and shaped based on the particular pattern preferred. Better have this done at the canine beauty shop, then later, maybe, take a few lessons from a professional in the acceptable manner of doing the work yourself.