There are two main principles to follow to avoid cracks in a baked cheesecake. First, avoid over-mixing the batter which will add a lot of air into it. The air bubbles will expand with the heat in the oven, making the cheesecake rise then collapse and crack. The second rule is to let the cheesecake cool down gradually. First, in the turned off oven (with the door slightly opened), then at room temperature and finally in the fridge.