The first thing you'll notice after zombification is the Hunger. You will never not be hungry for the meat of the uninfected, and will want to spend every minute eating human flesh, or when possible, brains, the caviar of human flesh. This hunger can never be sated, but don't let that stop you from trying -- in truth, a lot of the fun of being a zombie is in the trying.
And the lurching. There's nothing quite like a good lurch.
The problem with your new diet is the lack of necessary nutrients in human flesh -- a dietary deficiency which will be the cause for much of your bodily decay. You can retard this decaying process with proper nutrition, which sounds simple until you remember that any food that isn't human flesh will look about as appetizing as a cat turd to you. Fortunately it should be possible to trick yourself into eating something nutritious, as your intelligence will have decreased remarkably during the zombification process. By dousing foods in ketchup, you should be able to make them palatable to your blood-seeking stomach -- we use a similar technique today with children, also presumably because of their hunger for blood.
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With some pasta sauce on it, this looks basically like human brains.