Background: Current PGY-3 resident at a large, academic, university program. I've worked with many medical students, and here's some advice.
1. Be nice - As a med student, you are lowest on the totem pole, people will give you attitude, be dismissive, or may even ignore you. Keep your eye on the prize, becoming the best physician possible. Any amount of time you spend focussing on the BS, is time taken away for reading/learning/doing.
2. Show up on time - Actually, show up early, be prepared when rounds start to present your patients. When you show up, be ready to work. Don't show up, and then disappear to the hospital coffee shop, talk to friends on other services, or catch up on Instagram, come ready to work. Look the part, dress professionally, and know your role. If the attending, senior residents, and junior residents are all wearing white coats on rounds, as the MS3, you don't want to be the one person not wearing a white coat.
3. Know your patients. As a med student, you are carrying less patients than the interns, an probably the AI as well, so really know them. If your patient comes in with an AKI and the sCr is 2, what is their baseline? Do they have CKD? Look back in the EMR at old admissions if there are any, and if not, ask the patient who their PCP is, and call their office, asking for their last clinic note and labs to be sent to you at the hospital.
4. If you're on an outpatient rotation, take a look at the schedule for the following day, see what patients are coming in, read their previous note, and have an idea of what's going on before you even meet the patient. The last thing most patients want to do is have to tell their whole story all over again, so if you can walk into the clinic room, already having some grasp of what's going on, you will appear much more competent/confident, will likely gain the trust of the patient, and have a much more positive experience.
5. You can always learn - Even if you're dead set on doing internal medicine, and you're on a surgery rotation, you can still learn about things that will be important in your future career, eg: learn about the perioperative management of aspirin, anticoagulants, what is the literature on perioperative beta blockers? Who gets pre-operative ekg's? What are the ACC/AHA guidelines for surgery when you're on DAPT for a drug eluting stent? There are a lot of things an internists and surgeons can learn from each other.