Find the websites for each institution you're comparing. Find the faculty for each school, and look at their teaching experience, awards received, and universities at which they've studied. It's important to see who might be instructing you at each potential school.
Compare tuition and financial aid at each institution. Also research whether the European institutions offer grants or scholarships to foreign students.
Look at the extracurricular activities offered at each school, and determine whether they match your interests. Note schools that combine your desired coursework with clubs and athletic opportunities that suit you. Make a list of your top schools.
Contact an administrator at each institution and ask questions. Ask them to contrast their school with the other ones you're looking at. The ease with which you are able to communicate with leaders at the school could indicate the priority they place on student needs.