How to Network?

Basically the topic

I'm starting my sophomore year soon and I haven't really given much thought to networking and career aspirations until recently thus I completely missed out on my Sophomore year recruiting. I go to a highly ranked non target research school, my school has more STEM and Med school kids but not much interest in finance at the UG level but it does have a small B-school with a decent Postgrad program. (Think Case Western, URoch, Brandeis, Tulane). I don't have any flashy stats and my SAT is probably above average at best; 1400, if that matters.

I know people always say that you have to network like hell but I'm not sure how I should network with people, like do I just plain message them "Hi, I saw your profile on LinkedIn and saw that you work in XYZ and I'm interested" then set up coffee chats or what should I do? Most of the networking that I've done to date has been through college events with alums and they mostly work in tech and healthcare without much representation on Wall Street. Met just a handful of people that works in Finance out of hundreds and most started out in another industry before they went into finance, mostly PE though. 

Would love some advice on networking, my goal is to hopefully get an internship for the upcoming summer; which I know is already off-cycle thus the need to network. Would also like to use this as an opportunity to prepare and network for summer 2024 recruiting