We always went over the more common routines first: sequencing, coffee brewing, food handling/warming, etc. Then the difference in steaming milk for a latte, flat white, macchiato, and cappuccinos. Then we got them through the book before they got any more training behind the counter. The person that trained me in said they started this training routine because she noticed that when they (the trainees) have some knowledge of what goes on behind the counter, getting through the book is so much easier.