Let's break this one down:
Well, that last one sure must make it easy to forget yourself and concentrate on others. Or at least to forget your house. (Do you suppose Abnegation people ever wander into the wrong house by mistake, just shrug, and say, "I live here now"?) But seriously folks, what this tells us is that every faction lives in a style that represents and reminds what that faction is all about.
Those styles of life (or lifestyles) are totally different from how you probably live. Unless you live in a library. But this is why we think Divergent is pretty great: it takes things that we all know, like clothing and homes, and it makes everything a little more extreme, so that we can see the conclusions of these ideas.
We could go on like this for a lot of issues related to the factions—their symbols, their manifestos (printed after the novel), their haircuts, what symbols they use in the choosing ceremony—but it all boils down to some of the same ideas: