I wish I could share something groundbreaking that completely changes the game for how people think about expanding their network; but I'll be honest.
It's hard work. It takes time and energy to grow and maintain your network. You gotta put yourself out there. Attend events. Talk to people. Ask for introductions when you do meet with people. Stay in touch with your network.
I'll share one tip for when you do end up connecting with people. Figure out what makes your experience and skill set unique and create a point of view for how that can be applied to other CS teams. That will allow these networking conversations to be an exchange of value rather than one sided.