These are the things that have worked for me:
Start with the primary sources as early as possible - they will lead you to the theory you need.
Having a general sense of the territory is good, but read the theory you need to answer specific questions rather than try to understand ALL of the debates just in case.
Start writing early - like right now. Get an outline up as FAST as possible so you have some place to put all your bits and pieces of writing.
Engage with the material EVERY day. You must keep it fresh in your head so you spend your off time thinking about the issues. You cannot think through things if you have to spend the first five hours remembering what the questions are.
Find your minimal block of time to be productive - for me it is three hours unless it is mechanics. I can do mechanics in shorter blocks, and try to leave them for those times, and the times when I desperately need something hands on to do that will distract me and still keep me feeling like I am moving forward.
Have a space where you do not have to put your stuff away - unpacking every time takes at least an hour. I have a writing space where I ONLY do dissertation work. I have all my books out, my laptop and music and room for tea. When I go there I know I am working on the dissertation, and so does everyone else. I get left alone. I can concentrate.
Do no think you will remember where you saw something , you will not. Find a way to write it down, preferably a place you can find the notes later.
Write notes that are explicit enough that you will understand your line of reasoning a month later. Write it to someone else - that is who you will be a month from now. You will not remember, so don't write something to jog your memory - write something that makes sense.