After having my Sub-Internship experience, I would like to share some of my observations with you in the hopes that it will help you to avoid some of the pitfalls that I have seen. From the beginning of medical school, people begin telling you about the magic of 4th year. They tell you to hang in there with all the classroom time and late night studying during years 1 and 2. They say that it will be OK even though you are working 12+ hours a day during 3rd year. They tell you it will all be worth it when the 4th year comes along. We build it up to the point that when it finally arrives, we feel entitled to take advantage of the relaxed schedule and improved hours. But it's important to remember that while 4th year is (in fact) glorious, there is still some important work to do. The Sub-Internship is a job interview. Basically, you are sampling a residency program, and they are in turn sampling a potential resident (You!). With that in mind, here are some tips to help you stay on track to impress.
First, I made it a point to go in early and stay late every day. If you are tired, suck it up. I guarantee that the intern that you are working with has already put in more hours than you have. You want to show the program that you are a hard worker. Volunteer to help even if its outside of your comfort zone. I learned to dictate which is awkward if you've never done it before. But it is a skill I will need, and it was a small thing that I could do to help out.
Second, jump in on procedures and other learning opportunities. Be aggressive. This is not the time to be a fly-on-the-wall. As a Sub-I, you can function like an intern without having ultimate responsibility. You are first in line among the students for interesting cases and procedures. The faculty are likely to let you do a procedure that you've only observed up until this point. Seize that opportunity and show them that you are teachable. They do not expect you to know how to do a circumcision by yourself, but they do want you to be willing to jump in and learn.
On my rotations, I watched as students stood out for less than desirable reasons. Once a student mentioned that he really wasn't interested in doing OB in his future practice. Tailoring your practice to your interests is one of the great parts of Family Medicine, but when you are on your Sub-I is not the time to draw your line in the sand. You have a lot to learn and the least you can do is be helpful. Don't stand around simply because it doesn't interest you. Another student told me that I shouldn't work so hard because I'm a 4th year student. Do NOT fall into this trap! I think about the residents working with me. I want to try to work as hard as they are working.
Be careful about your interactions. Use good judgment and conduct yourself as a professional at all times (even socially). A good rule of thumb is don't order alcohol when you are with residents. Be careful about your social networking. You can add new resident friends on Facebook, but be sure that there is nothing on your profile that will make you look bad (drunken pictures at the bar, crude wall posts, etc.).
Finally, write thank you cards to the people that you worked with, especially if you are interested in their program. It shows that you are grateful for the time that they invested in you and you are a thoughtful person. Do this and you will make a great impression while having fun!