Note, it has to be 100% ACRYLIC YARN or else this won't work. That's because stuff like cotton yarn will brush out as soon as you start brushing.
This is an easy process, but it takes a loooonnggg time. If it's a tiny little tail for a keychain like the one I made it'll only take a few hours. But if it's super long like for a big scarf, it'll take much longer. The long white and orange one I made for a pokemon costume took about 3 days of solid work. Also get creative with this. You can make keychains, tails, phone charms, scarfs, anything!
Note: I added a bunch of steps just to kinda keep people from being lost. It's much easier
(I originally got the idea from Bir's yarn tail tutorial. But I altered the process a bit to make it quicker.)
~MAKING THE BASE~
Measure about how long you want your tail. Then add about 5 more inches onto the length for a small tail. For a large one leave about 10. Don't cut it off yet. Do this in the color you want the tip of ur tail. For this I'm making a black fox tail tipped in white.
(I actually had already began making a tail before I decided to make a tutorial on it. So this one is just a little quick one I did for the tutorial.)
Next use the slicker brush, don't worry if lots of the "fur" comes out when you brush it. It just happens. When I did my big tails I had trash cans full of it! If when you're brushing and so much "fur" comes out that the tuft of fur shrinks and grows small, then your yarn isn't 100% acrylic.
~MAKING THE FUR~
(pop in a movie or 7. It'll take a while.)
Now next we're gonna start on the fur. Note, this is for makign ONE tuft of fur. You're gonna wanna do this AT LEAST 40 times.
I actually got my black yarn from a scarf I was pimping out to look like a fox.
To measure out your fur you're gonna wanna take the yarn and wrap it around your hand(or can if you have small hands like me). For a tiny tail like the one I'm making you'll wanna do it about 5 times.
Also, if the yarn you have tis thick, you'll wanna do it about 5 or 6 times. If you have thin yarn, up to 15. Regular, 10. You don't want the knot from where you tie it too big, but not too small either.