Hello. I believe you are being asked to take notes that will help you to track the development of Maya agriculture. In other words, what are the events that helped Mayan agriculture to develop? Using a sequence chain, you can write down a series of events in the order in which they happened (for example: 1. I ate a whole bag of chips -> 2. I got a stomach ache. -> 3. I had to go to bed. -> 4. I missed out on going to my friend's house). One event leads to another.
I hope this helps!