It is a good idea to take the expansion board as soon as you can. You get points for for filling the expansions, so use it from the start. Don't focus on the expansions too much. You might lose track of what's really important - your animals. Letting your animals run away can sometimes be a good strategy if you see that your opponent needs those animals for a high score. Yes, animals will go back to the stock, but your opponent will have more trouble collecting them. Horses are among the best breeding pairs, so try to get them as soon as possible. They reach one point per animal faster than the rest. Your first move should be either collecting three units of wood, or collecting one of wood, stone, and reed each. Trading stations are very useful as you can build them and use them in the first round. Try to avoid the Assembly Hall. It will do you more harm than good.