Having a rigid structure of following up with people feels and comes off as fake. Just befriend people whenever you can and be helpful. Think about how you connect with say some school or college senior you meet or text after a long time. I don't think 'networking' needs to be any different. I cannot overstate the value of being nice and helpful to people at places you have interned at (its miles better to be on good terms and count them as friends for sure).

Hi, I am in my first year and I always hear people saying it is important to stay in touch with people in the legal field, for eg : the people who you've interned under or the people you've interacted with during an internship at a firm, how exactly are you supposed to that ? Are you supposed to send an occasional how are you message or .... ? Any guidance would be highly appreciated thank you!