A small warning, and a tech as well.
Recently, I posted techs for shamanism, and I'm willing to bet that people are trying them out. However I should've warned you about how much energy it takes to maintain the synchronization. It requires a lot of energy to maintain this, so please, start extremely small, because I don't want anyone killing themselves trying to learn shamanism.
Now that that's out of the way, I'm going to explain how to talk to animals through this. However, I will warn you. This isn't an easy thing to do. Some might compare it to telepathy, and if you wish to do this, then by al means fine. But the thing with doing this is the more instinctual the creature is, the easier it is to maintain this, but I digress. Anyways, all you do is reach your mind out toward the animal in question, and you can understand what they say, and the can understand your regular talking. However, if you want to have the talk mentally in order to avoid strange looks( someone might try to throw you into the funny farm if they see you talking to an animal like one would talk to a person), by all means fine.
Anyways, this concludes my article. I how that this article has been informative and entertaining, and wish you luck in all of your endeavors.