Starting up my own consulting business

I am starting up a Consulting Business.
We’ll do install, h/w and s/w, programming, project management, implementation and conversion.
Any advice on startup or what to watch for?
I have not yet built a client base, but I references available, that could be potential prospects and/or networking groups when I begin.
I have the h/w, s/w, programming, business plan, license, all the goods (except capital $).