There are two different ways to approach the structure of an essay that compares two texts. One is an integrated approach, and normally reaches the higher bands in mark schemes as a more sophisticated approach, and the other is segmented. You can either make your points about each text separately, and bring them together and compare them in your conclusion. Or, preferably, you will make a point and compare the two texts side-by-side in each paragraph, and then summarise your conclusions at the end. For example, Cold Comfort Farm and Sons and Lovers are both texts that heavily emphasise the effect of setting on its characters, however, in Cold Comfort Farm this is parodied for comic effect.