Even though I'm a newbie here, I did have some game developments in the past when I made Flash or Director game projects.(personal & academical) I might have something to give. Here's my take on how to manage time, especially for those making bigger than casual games: (excuse my meticulous writing style
At the very beginning of development there's excitement. you have the most enthusiastic mood and your brains are more relaxed, which is perfect and ready to bring ideas to the table, as well as learning & making tests and prototypes. There should have no strict deadlines at this period. Take your time, cos' ideas & concepts can't be rushed.
Second, when you start coding or putting art/design/audio assets for the game, is where you start feel like "working".You should have a time-table & deadlines. At this stage you should probably planned out all the major stuff & minor stuff, the 'to-do-list'. Also, It's always more productive when you have deadlines
, they can be quite a motivator!
Now, get the "real work" started & do all the major workload, the things that most people would notice and expect. Try to get yourself into this "creative flow"
, once you have it, don't stop! You'll be amazed of how productive you can be. This stage can be more flexible than you think, just try to do all the part you're eager to do at the time being, and leave all the repetitive & similar elements (art assets like: grid sprites/letter designs/in-between animations etc.) to the next stage.
Near the end of the development, we usually have most of the game elements finalized, that's where 'Crunch Time' is at. Get a complete work list, and be in total focus, no distractions, and work like a machine! Compress workload into a short time, 2~4 days is the limit. Crunch Time is not
meant for making up new idea or planning stuffs, you shouldn't use more brainpower in crunch time or you'll get even more exhausted, or even frustrated, which is bad for work. Just complete all the stuff in crunch time, and get them over with quickly.
Then lastly for the remaining parts: fixing, debugging, optimizing etc. It doesn't matter 1~2 weeks or extended, you're nearly finishing your game, so relax and use as much time you left for polishing the game, before proceeding into publishing or marketing stage.
Overall: I can't stress enough the time management used for different stages of game development. Moods, on the other hand, is also quite crucial. What's the point if you feel making game is like being in a battlefield, hard & gritty...
Sorry for the long comment. I hope I wrote well for my take.