AMI training is structured a bit differently, but perhaps this description will be somewhat relevant.
My training was a full academic year (August through the end of May) in the evenings (I can't remember the times, perhaps 6 - 10pm?) during the week. I think that it was four days per week, and every other Saturday all day. This was almost 13 years ago, so I may be a bit off on this.
We did several weeks of observations, a hundred and something hours I think - I can't remember exactly, and then several weeks of internship in three (maybe two, but I'm pretty sure three) different locations each. (perhaps three to four weeks each of three internships?)
We had to write our own albums (books with the presentations we offer the children as well as theory) in each subject area. The teacher trainers give the lectures and present the materials, we take notes and practice the presentations with each other, and then write up the presentations and submit them to be checked before they go into our album. The idea is that if you write it yourself you will remember it better, rather than giving out copies of the presentations directly to us. We also had to illustrate each activity. It was a lot of work, but worth it. I love my albums and treasure them and use them all of the time.
I have many albums from the primary (2 - 6+ years) training:
Exercises of Practical Life
Cultural (includes art, music, geography, biology)
I think that these albums are what is meant by "making your book" but maybe not.
We also had to make some classroom materials.
At the end we had written and oral exams.
It was a lot of work and I admired the people in my training who had children and still managed to get the work done, no easy feat!
Good luck! I'd love to hear how it is going!