Let's break it down. First off, it is a simple restatement of Pascal's Wager. The wikipedia article makes for good reading.
But here's my own simple analysis. And I'm no Pascal, but I'll try anyway.
First off, and not to be picky, but why is it in quotes? Did somebody actually say this? And if so, who? A great inspirational leader I suppose. And if not, perhaps the sign maker? Pretty sure it wasn't Jesus.
Basically, what it says to me is that I would rather live my life with one set of beliefs only to find out when I die that they were wrong, than to live my life with a different set of beliefs only to find out they were also wrong. And that just sounds absurd.
Stated differently, "I'd rather live my life thinking I'm right and die to find out I'm wrong, than to live my life thinking I'm wrong and find out I was right". It's just mixed up and crazy when put like that. Not so inspirational now, I guess. So let's move on.
Next, the statement itself requires that I will live past my own death to find out whether I was wrong or not. Well, that seems absurd. But let's make that part of what belief in god is, remembering that not all belief systems require and afterlife. "I would rather live my life as if there were an afterlife and find out there is not, than live my life thinking there wasn't and find out there was." Ah, there's some meat on the bone at last. But again, if there isn't an afterlife you'll never know it. If there is, then we're back to Pascal's Wager, an absurd paradox.
So let's take that out and have it read, "I would rather live my life as if there is a god, than to live my life as if there isn't." That seems more straight forward. But then you have to ask what god, or which god, and does it matter? Can you choose your god? There are quite a few of them, and even quite a few interpretations of something so seemingly fundamental as the christian god. Again, it gets very confusing.
And how would your life be different if there was or was not a god? How would you live differently in either case? Maybe I'd be forgiven for my trespasses or something. But I live a good life and I don't have all that many trespasses to worry about. But maybe it's different for you. I'd like to know.
In the end, the truest words in this sign are the first six. "I would rather live my life". So I'll go do that now.