I don't think you can find detailed information about that in the guide section. Probably because there are several different strategies that will work. My strategy is to keep the population low and put everyone except one farmer on research. And then get enough tech points for both farming level 2 and construction level 2. After that I put all the scientist to get tech points for level 3 farming. During this procedure I keep the population below 15 villagers in order to have enough food for them.