Though Scotties are fairly small, their coats can get pretty long (and turn into tangled, matted messes)--so Scottish Terrier grooming needs to be a regular practice. Dogs of this breed also react very badly to fleas, which can cause them to chew their skin nearly bare; it's a good idea to get a flea collar for the dog and a flea comb to use intermittently when brushing.
Brushing should take place 2-3 times per week (and daily if your Scottie is a show dog). First wet the coat with mist from a spray bottle, then use a pin brush to "line brush" the dog; use a wide-tooth comb on the facial furnishings and leg and underbelly hair. These dogs have dry skin, which can get irritated by baths; hence, follow your Scottie grooming session with a bath only once every 6-8 weeks, or if the dog gets particularly dirty.
Depending on your preferred hairstyle, Scotties will need to be clipped every couple of months; they may also need to be stripped (whereby the dead hairs on the outer coat are removed) twice a year. The clipping and stripping can be done at home, but it might be good to make at least one visit to a professional groomer; the groomer can clip and strip the animal, and share other advice on how best to groom a Scottish Terrier.