How to learn to chant the Liturgy of the Hours?

I went to solemn vespers for the first time in my life last Friday and it was super awesome. I brought my liturgy of the hours book with, thinking I might need it, but they provided a card with the whole thing on it. Complete with some sort of music part where one word was underlined and it corresponded to what note to change to. So it was like "Lord come to my assistance" and "assist" was underlined because the pitch changed there. So, my question is, since my breviary doesn't have that cool stuff in it, how does one learn how to do it? For both personal recitation and for leading small groups in it? Are the pitch changes solely based on the meter? And why do we switch people intoning the words every other line? When doing small group Liturgy of the Hours, we usually break it up into the paragraphs.