First off I'd find myself a suitable base, something like an empty warehouse (there are a lot of them around my area). Then I'd go pinch a large van and start stockpiling resources. Food, water, portable generators, survival kit, petrol, that kind of thing. I'd also take advantage of the remaining few days of internet to print off anything I needed to know or wanted to preserve.
Stage two, once I'd gathered a fair amount of resources, would be to begin a project, 'cause I need to keep busy otherwise my mental state tends to deteriorate. This project would be building living quarters in my shiny new warehouse. During that time I suppose my routine would consist of a little construction and a little learning (how to farm/hunt/live without electricity etc) daily, with breaking into houses on days off. I'd be primarily gathering books, food, and other handy things (like maybe a nice sofa or bed or something), but I can't pretend I wouldn't snoop.
Stage three would be exploration and planning for the long term. I've got a van, a bike (and believe me, I would have stolen several incredible bikes by then), a map, and the whole of Britain. There are places I'd love to go, mountains I'd love to climb. During my travels I'd be on the look out for somewhere perfect, somewhere I can settle and farm (and assuming animals haven't vanished, it wouldn't just be rearing veg and the like). I would return to my warehouse either every weekend or whenever my van got full, whichever comes first.
Stage four could be a long, long time down the line (assuming I haven't gone nuts or killed myself). It would see me in that perfect place, a house with solar power, plenty of storage space, a working farm, and one hell of a library. From there I'd live out the rest of my days, continually reading, learning, and keeping myself as physically fit as I could stand (because I actually find that fun, so...). It'd probably cross my mind at some point to actually try and document history and speculate as to what happened to the human race, then bury it as a time capsule for future archeologists to find.
...heh, I enjoyed planning that far too much.