Columbia SIPA?

Hi! I’m currently an incoming freshman at George Washington University majoring in political science and minoring in international affairs. I’m considering graduate school after college for a multitude of reasons but SIPA is by far my favorite program. I just wanted to ask what do you guys think I should do in college specifically in order to promote my chances of getting accepted to SIPA? I understand having experience in my field after graduation is important but I want to take this step by step and know what I should do going into college. Does anyone have any advice GPA wise, extracurricular wise, rec letters wise, or just a general outline for preparing for grad school? Thank you!