Think about "what is assigned."
Show up every day. (duh). On time would be nice. Dressed properly is good. With the correct equipment (you laugh, but I worked with another student who showed up on medicine without a stethoscope). Be polite to the patients and the nurses. Ect.
Think about "more than asked."
Consider...when it is 5pm and everybody on the service is tired...and there's three new admits coming in, volunteer to stay and take a history.
Take it upon yourself to make three patients on the ward "yours" and talk with them (or with the parents if it is a peds patient).
If you are allowed to write notes and you have written on these three patients, and then it's 2pm and the notes still aren't done, volunteer to go and write notes on two other patients.
Assigned is people knowing you showed up.
More than asked is people knowing you helped out.
Acting like you're interested (not phony "oh, I've always wanted to be a whatever) but "show why you chose to be a pediatrician/surgeon/pathologist" is appreciated.