How to network with small regional boutique

Hi Wall Street Oasis,

First time posting here so please don't be too harsh

A brief background about myself: I am currently a junior at a non-target school, striving to break into investment banking. I have prior experience working at a small PE shop, which has provided me with familiarity with the deal process on both the buy-side, I have a very concrete idea of what the sale-side does thanks to discussions with peers and professionals who are in the industry. Additionally, I will say my technical aspect is decent thanks to all the financial modeling and PowerPoint courses I took, combine with WSJ and other resources out there.

Realistically, I understand that breaking into bulge bracket and middle market firms will be a journey for me over the upcoming years. Therefore, I believe the most best approach is to target smaller regional boutique shops.

I have some questions regarding the networking approach specifically tailored to small regional boutiques. When initiating initial email outreach, what structure do you recommend? My previous attempts have resembled coffee chat invitations, I tried indirect communication and requesting a career conversation. However, these attempts have yielded low response rates. So I want to get some insight before more unsuccessful attempts.

Furthermore, whom should I be reaching out to? I have attempted to connect with analysts/associates at boutique firms on LinkedIn, but few have accepted my invitations, and even fewer have responded to my messages. I have also tried sending more general messages through their infobox.

Any wisdom and recommendation will be very much appreciated, I am grateful for you all taking the time to respond to my prompt.