Here's a little piece of heresy: that means that we should be full of ourselves. We look like god, we know good and evil like god, yeah?
No. If anything, it's a weighty responsibility, not a liberating license to self-worship. Just like children to our earthly fathers, we have the option of being obedient and bringing joy to our father's heart, or bucking authority and hurting the one who loves us the most.
Here's one that combines this idea of image-bearing with the idea of sanctification (through the work of the Holy Spirit becoming more Christ-like, loving others, seeking purity):
First we're children of our fathers (both parents, but fathers for the sake of this analogy)
Then we're adults
Then we're a married couple
Then we're fathers of our own children and the cycle begins again
As children, we learn what it is to submit to a father (or step-father, or father figure, or mother who has to take up the paternal role for whatever reason).
Hopefully by single adulthood we've matured and learned from our adolescence, and we are then vessels of the Holy Spirit (assuming you're a believer). As Christians (a word which means little Christs) we are all extolled to emulate Christ and allow the Holy Spirit to work through us.
Marriage is a picture of how Christ loves the church (in this case church means the universal church). Wives submit to your husbands (the church submits to the authority of Christ), but I would say the part that gets overlooked, not said enough, and sometimes even ignored is that husbands are to be Christ to their wives. Going back to my first point, does that mean treat your wife like a slave and just accept her submission? NO, absolutely not. What'd Christ do for the church? Gave his life and even still loves, serves, and comforts. That's what husbands are supposed to be. In a sense husbands are to be image-bearers of Christ.
Now the last one is more obvious, fatherhood. God disciplined his children (Israel in the old testament), but never stopped loving them and working for them, even when they were disobedient, riotous, and self-destructive. Men, you either are or will one day become fathers, and you aren't supposed to give your kids a bad example so they know what God their Father is not, but you are to bear the image of God for your kids to know "God loves me unconditionally like a father, like my father."
In other words, by the time you reach fatherhood you are to be vessels and tools of the Holy Spirit, Christ to your wife, and a good father to your children.
When I hear the phrase "God created man in his own image" I don't think that God's form is limited to a human-esque appearance, or that I'm some how more important because I'm in God's image, I think that it's a statement outlining the lives we are to live, the stature with which we are to hold ourselves, and the responsibilities and commands God has given us.