What would be some tips for a B2B business to grow a community before a PH launch?

My name is Puiu Mihai. I am working to open a branding design studio specialised in a specific B2B niche. I was really wondering, when you start from scratch, how could one grow in people’s eyes and gain their thrust to start supporting him. I am optimistic that my plan would be simphatised by some people, but in B2B market i feel like is a bit harder to convince without delivering anything, considering how fast paced things must go. Thank you in advance for any useful advice!