Section out the pieces of your hair you want to turn into coontails. Make sure all of your remaining hair is pulled back tightly and out of the way. If you have curly hair make sure you straighten it before dying to make things easier.
Now prepare your stripes making stencils out of scotch tape. Put pieces of tape across the strand of hair you are going to dye from top to bottom. You should make them no more than 1-3 inches apart in width. Once you've got the tape in place secure them by wrapping them tightly around your hair. Don't worry this won't pull your hair out afterwards.
Now apply your hair dye to the exposed areas on the strand of hair. You can apply the dye easily with your fingers or a dye brush. Be sure to saturate the exposed hair and try your best to not let it seep under the taped hair.
Wait for your dye to develop. The time you have to wait depends on the dye you bought so be sure to read the directions on the box.
Now you can rinse any excess dye out and remove the tape. Dry your hair and enjoy your new fabulous coontails.