As much as you want to sell your self in a good light, do not make the mistake of exaggerating your current position. Add some of your routine tasks to make it realistic and do not neglect things like paperwork. Try to be in the interviewers shoes as you answer this question. A job you have been doing for years should be part of you already and as such; you must know all the tasks you undertake. Try to show them that you plan well before you begin work and after you attain your goals, you review the process to see how you could be more efficient.