I am a big fan of breaking large projects into bite sized, easily manageable pieces. Call them phases, stages, parts or what have you; it is all the same. The point is taking something that has a deadline far in the future with a million to-do items and turning it into something that has short deadlines with easily managed and concise deliverables. To effectively accomplish this you have to sit down and have the big picture discussion with the end goal clearly in mind and plot your course to completion; this is where I find lots of projects get tripped up. Even if you have broken it down into 2 week deadlines, you still have that looming 3 month deadline and waste time on the overhead of having to meet deadlines to meet other deadlines.
This is why I like to use the Phase Now and Phase Later approach. Why not have that big picture discussion and compile a list of concise, clear deliverables and then sort it in order of priority. Once you have done this, put as many priority items as you can in comfortably manage with a short deadline (couple weeks) in a separate list and call this Phase Now; everything else is Phase Later. Get the most important stuff done first and then keep moving down the list from there. Of course this does not work for every project and in every instance, but I have found that things tend to get done quicker and lots of time is saved by not having to implement unimportant details upfront.