Okay, first of all, I know that, for at least half of the day, you can’t avoid light, unless you stay inside until sunset. That is not what I’m talking about. What I’m talking about is avoiding light once night falls, or at least, avoid it as much as possible. I wouldn’t be walking into pitch-black alleys any time soon, but, think about this: In the middle of the dark, if you turn on a flashlight, where do you think every zombie in the area is going to go? If you guessed “Towards the light” then, congratulations, you guessed right! Your prize: Getting your face gnawed off by the dead.
How to avoid it?
Well, this is tricky, honestly. Again, stumbling into total darkness is NOT a good idea, and not having a flashlight is not a good idea, either, but, as I said, if your city gets overrun by the dead, any sudden appearance of light will surely draw them to you.
So, depending on how early into the apocalypse we’re talking, your best bet will be to rely on the light that’s already available to you. If there are any streetlights still working or, possibly, fires raging, try to use them to see as much around as you can before moving on. If you’re really lucky, The Moon can actually provide you with a decent amount of light, certainly enough to see any zombies that might be roaming around.
Lastly, if you absolutely must do it, use your flashlight to see what’s ahead of you as quickly as you can, and then, shut it off. Like I said before, every second you leave it on more than what you need, is another second the dead have to try to track do the source of that light, a.k.a., you.