I did the same for the web development world and can share with you my experiences. I too loved what I did so much that I, and several other developers, got together to form a web development agency.
We started out by:
- Quitting our jobs, so there was no conflict of interest, though the others retained part-time contracts until our revenue stream was stronger.
- Contacting our network to look for clients. We did this before we even had a website or logo, though we did come up with a name.
- Contacting our network to look for more developers. Once we found our first client, we started building out our team with people we knew & trusted.
It wasn't until we secured our first client did we start doing all of the other formal steps, such as design a logo, incorporate as a business entity, build a web presence, formalize a pricing strategy, formalize a sales strategy, formalize a recruiting strategy, formalize a development process, etc.
The reason for this was to determine if our services were marketable & desirable. We initially thought the market would be saturated with web development agencies. This proved that, yes, there was a need that we could fill. And fortunately, we've been profitable since then.
I hope this helps. Good luck!
P.S. It also helped that I had co-founders and a division of roles. I focused on business development and project management (though we later hired a dedicated project manager). Another co-founder focused on streamlining our development process. The third focused on being a technical lead for our client projects, to ensure quality. It may not be necessary to have co-founders, or such a division, but for our situation, it helped.