This is a quick and easy way to get a nice carrot tail on your pet trims in the salon. If you are hand stripping or very familiar with Terriers, you likely already know the ins & outs of quickly producing a proper tail, so this tip is more so for saving time in the salon.
First trim in your pet pattern as you normally would--whether just a heavy card or a clippered back, remember to always try to at least do a good amount of carding before and after clipping a harsh coat to help keep some texture and benefit the skin. Also remember that a skip tooth or "S" blade with uneven teeth will give you a more natural finish than a finishing of "F" blade. A #3 3/4 Skip is my favorite blade for a pet trim as it leaves enough texture and un-evenness to card and thinner out really nice.
When you go to do the tail, use the same blade as you did on the dog's back. Unless you've used a #7! If the dog is clipped in a #7, go up a couple of blade lengths to about a #4, and just do the entire tail, and then thinner it heavily to take out bulk. You can thinner the underside to remove any poof with your blenders instead that running a #7 up the underside as this will flatten your tail. Be sure to check that the dead hair is also removed from the top and sides of the tail- using a Coat King carefully or another carding tool will do the trick, and get the tail to lay a little more tightly. The idea is to create a natural looking tail that adjoins the body without a dip at the base of tail from the croup, and to have no flag on the underside of the tail; but a tail which adds no length to the dog's back, and completes a level, solid topline. The hair should be hard and of uniform length. The tail circumference should be proportionate to the rest of the dog, not too thick and not too thin--but "slender" is good. By taking the hair on the underside of the tail short, be are actually shortening the perceived length of the dog's back and its frame.
Clean and combed tail ready to trim.
Setting the length of tail. I do this with blenders about 1/2" from the tail tip. If the tail is thin or scarred at the tip, do not scissor too close. Please excuse those hard working hands!
Drawing the tail straight down and slightly out from the rump, stand over the top of the dog to see where the sides of the tail need trimming to begin to bring the base of the tail in towards the tip. With the tail in this position, trim each side in a straight angle from tip to base, wide at the base and similar to a short, "robust" carrot. You should blend the hard lines off with blenders or thinners to create a natural look. You now have the underside and the sides of the tail trimmed, what's left is just blending and contouring the top side of the tail to complete the carrot shape.
Keep the tail in the down position, holding it straight all the while you are trimming. Now shape the top of the tail thicker at the base and straight out to the tip. Be sure that there is "cushion" at the tail base so that there is no dip off the croup where the tail adjoins the body.
Now lift the tail over the back to see that the hair on top of the tail base isn't too thick so that it poofs when the tail is carried up. We want a level topline and a back that looks sturdy and not too long.
Remember that when finishing your dogs, you should always double check your work in front of a mirror if possible, with the dog standing as squarely and stacked as it can, in their typical breed standard stance. Learning to take a good overall look at your dog will help you notice little things you may have missed. And don't be afraid to let them have a walk and a shake and then re-stack them to see what their movement may have moved or settled on their clip.
Notice below how the carriage of a tail alters the topline and overall appearance of the same female dog. The same dog at 12, 1 and 11!