In order to choose a program that ideally suits you, you will first need to define the goals you would like to achieve through the experience. For example, would you like to learn a language? If so, then you should not choose a program in which the courses are taught in your native language or in which you spend most of your time with people from your own country. Are you looking for an opportunity to travel? Then finding a program in a fairly central location with good public transportation and ample time off to travel is an important feature for you.
You should also explore how program offerings apply toward your degree or to your education as a whole. Does the program relate to your major (if you already have one). Can you take courses that will apply toward major or general education requirements? Does the program give you the opportunity to take courses you might not otherwise have the opportunity to take at home? Are there extracurricular offerings -- organized field trips or pre-program intensive language immersion courses, for example-- that can enhance the experience?
Finally, depending on your degree of personal independence and comfort with the idea of going abroad, you may prefer a program that has a strong orientation component and an on-site support network for international students, if not just for students from your particular school.