Entering absorption can be a slippery slide, especially if you don't have someone experienced nearby to help guide you. If you are new to meditation and trying to learn from books or the Internet, while some people with highly developed intuition may be able to somewhat accomplish this, the vast majority cannot. You're better off studying with someone in person, especially in beginning a practice, who can help you to make corrections "on the fly."
But, if you are bound and determined to try this on your own, then, tarin pretty much covered it. Especially when he mentioned:
"tranquilise the feel of your body by paying attention to it along with the breath. that is, feel the breathing of the whole body with the whole of your mind."One antiquated method of doing this was mentioned some twenty-five hundred years ago by man named Gotama (his family name). You may have heard of him in your research. Anyway, what tarin recommended is almost word for word, thought for thought, what this man recommended. And I should mention that this man was an expert at this. So, he knew what he was doing and pretty much how to explain it to others. Fortunately, we still have some of his instructions recorded from history. A modern monk, Thanissaro Bhikkhu, has kindly provided a translated version of this method in his book
Mind Like Fire Unbound. If you will read the section titled
Habits & practices, you will find this method described there, almost word for word. It describes in a little more detail what tarin was attempting to communicate to you.
Good luck to you, Zach. You're going to need it.