I feel you, apotheosis! My biggest problem was staring at my data for literally hours, then typing a sentence, sighing, and giving up for the night. Most of my tips are probs a little obvious, but...
To minimize distractions, I am madly in love with SelfControl (http://selfcontrolapp.com/).
To get my blood flowing to the brain, good music without lyrics (I vote Tchaikovsky's violin concerto in D minor).
To make myself actually produce words, I was a big fan of working with someone else. By that, I mean sitting with one of my insanely patient, awesome friends and working with them literally beside me. They helped me by making me feel like I had to be productive because I was in front of someone (the pressure!), doled out hugs and encouragement when needed, and nagged me when I got distracted/didn't write for a little while/tried to slack off. Also, I found it useful to have someone to talk through my thoughts with when I hit a wall and didn't even know how to make heads or tails of where to go next (although given that my go-to work enforcer is an engineering student, by that I mean talking at him while he looked vaguely bemused at how animatedly I was ranting about conservation legislation). But then again, I'm a very verbal learner, so talking through my data was immensely useful in terms of organizing my thoughts and helping me move forward on the actual thesis.