Break each section down in an organized system hitting the main points : etiology, pathophysiology, medical interventions ,nursing interventions, patient teaching ,solid knowledge of medications and interventions with knowing the expected outcomes of treatments and adverse effects/complications associated with them. Patient teaching is key . Be able to explain everything to a patient. And do practice questions as much as you can. That's how I approached Med Surg,finished with an A and 100% on the final exam. You can do it. Just stay consistent and have a good study method.