I have two different ways of working:
1) Work everything out, and pin every feature down beforehand. This is definitely the best way to maintain sanity and ensure that you are all singing from the same hymn sheet.
2) Sometimes I work with artists who cannot work with the above scenario and may want to make changes at any point during or even months/years after initial development. In this scenario I often think about myself (and possible changes) in the future. I keep things loose and build in flexibility right from the beginning. It doesn't always work but it does help. I even make it possible for the artists themselves to make changes (adjusting INI files and the like), so that I can guide them remotely.
1) Work everything out, and pin every feature down beforehand. This is definitely the best way to maintain sanity and ensure that you are all singing from the same hymn sheet.
2) Sometimes I work with artists who cannot work with the above scenario and may want to make changes at any point during or even months/years after initial development. In this scenario I often think about myself (and possible changes) in the future. I keep things loose and build in flexibility right from the beginning. It doesn't always work but it does help. I even make it possible for the artists themselves to make changes (adjusting INI files and the like), so that I can guide them remotely.