I'm so sorry @TheAnimalIHaveBecome easter stuff -.- okay well I'm pretty sure you wouldn't like to fiddle with trying to reach me for a few days so I'll help as much as I can.
When trying to get a tail phantom I will think of a time my kin had gotten her tail stuck (in your case you can even make it up or ask her for a memory) and recall it like it had happened to me. I'll think about the feeling I would get and after a while I will start to feel the familiar tingle at my tail bone. the rest comes after that.
When I want a ear phantom shift I will picture what the animal side of my ears look like (my animal side not my kin's; Leesha's. Then I will imagine what life would be like if I constantly had those ears (real not fake) and what daily life would be like that if they were permanently there. This can take anywhere from 5-30 minutes. Once I snap back into reality I will often feel my ears atop my head, my ear phantom shift.
I really hope I have helped but keep in mind these are all my ideas. I do not look it up as I find internet extremely useful but also very unreliable. Anyone can say stupid things and act like they know what to do, when they looked it up as well. Look it up if you desire but I think my way may help you more, coming from a real therian with their own idea. If you have more questions feel free to ask; I love helping others and even listening to their problems :)