A Wire Fox Terrier has a dense, wiry, medium-length coat that can get tangled or matted, so Wire Fox Terrier grooming is an important step in keeping these dogs looking sharp. They will need brushing once or twice per week, and baths every 4-6 weeks; if you merely keep your WFT as a pet (and depending on your dog's hairstyle), it can be clipped about every 3 months, but show dogs will definitely need to be stripped/plucked, which will leave much of the outer coat on the dog. (More details on the stripping process are in the "Plucking & Stripping" section.)
Brushing should happen 1-2 times per week; you'll need a slicker brush, a medium-tooth comb, and possibly a mat rake to work through any stubborn mats. First wet the coat with mist from a spray bottle, then use the slicker brush to "line brush" the coat, brushing in the direction of hair growth. Then use the comb to go through the head and ear hair and the facial furnishings. If required, work through any mats with the mat rake or your fingers. If you're following the brushing with a bath, use canine shampoo (available at pet stores), then towel- or blow-dry the coat; finish with another quick brush-through to neaten the coat.
Whether your dog needs clipping or stripping, it's recommended that you have the procedure done at least once by a professional groomer; the groomer can instruct you on doing the clipping/stripping process yourself, and can give you tips on how best to groom a Wire Fox Terrier in general.