I don't work in your field (although I have some of the same skills) and I thought I'd share my experience over the last couple of years.....
I've been self-employed for 9 years and made a pretty good living from that. Over the last couple of years work and opportunities have certainly declined, as people say things are tough out there, and in my financial year 2009 - 2010 I only made about 2/3rd of the income (and profit) compared to previous years.
However, what I did find was a new opportunity, using the skills I already had, which I found I really loved. And in the space of a year I am well on my way to having a full time income from that. The interesting thing is that this in not a brand new niche, it's been around for many years, and there are already people established who work in this area. Some others working in this area have spoken to me about how tough things are, yet I have been able to generate interest and work and even to pass referrals on to some others already established in the field.
So how? Well I'm not doing anything miraculous, or devious, or anything that takes work from other people (in fact as I said already, I've generated some additional work for them). I think it's just that I've got a set of skills that is right, and I've got energy and enthusiasm for this work (both for doing it, and for marketing it). I think that in some ways I am a fresh (or naive?) pair of eyes into the market so I see ways to interesting people that others who have been working in the area for much longer have either disregarded (they may not have been the right approaches at the time) or which have required an investment of time/money that they have not had.
Your original post asked about developing your business over a 2 year period. I guess that some of the success of this will come from how much you can put into it. It will be easier if for example you are currently a SAHM earning no income, with children at school - so you have time to invest without needing an immediate payback. It would be much harder if you were already working full time, and trying to build your business in the margins of your life, or having to make choices to lose a day's pay in order to market and develop your new business. Does that make sense?
So my advice, fwiw:
- get really in touch with what you are passionate about and gooed at (don't dilute your efforts with things that you might be able to do also but are not really driving forces for you).
-have a plan, follow it, work out what is working and do more of it, be honest about the things in your plan that seemed like good ideas but you don't really feel motivated to follow them through, and keep a flexible mind so you can develop a specialism if it arises.
- listen more to your own intuition than to the voices of others, have confidence in your own conviction, AND also heed the advice of others where is of help.