There are a few books on the market but, of course, all assume that the reader has some familiarity with natal astrology.
I'm actually currently reading 'The Art of Forecasting Using Solar Returns' by Tony Louis which seems quite good and does explain some of the basic ideas. I'll report back on it in more detail, when I finish reading it but a couple of general points to make are that solar returns, like other forecasting methods only show when the natal promise is likely to be released. No matter how much your solar return seems to indicate that this is a good year for business, if your natal promise does not indicate that you will be highly successful at business, you're not going to make a fortune this year. The point is that you need to read a solar return chart in conjunction with the natal chart.
Secondly, you will also need to consult other forecasting charts, such as secondary progressions, transits, and lunar returns (and indeed other planetary returns) if you are going to get the most out of them.
A traditional Astrologer would use solar returns (which used to be called revolutions) and primary directions and possibly one or two other techniques in order to make a predction for the year.
Edited to add:
There's also a book by Janey Stubbs and Babs Kieby, which I think is still in print. It covers both Solar and Lunar Returns. It is quite useful but is rather weak on theory as compared to Louis, who is also more practical as well!
It's worth also pointing out that there is quite a debate about whether to use tropical returns or to adjust the returns for precession of the equinoxes. There have been some good threads on this aspect by Dave, (Dadsnook200). Louis acknowledges the debate but does not try to cover the issue in depth.