Take a moment to look up your local sex offender registry.
I was shocked to find out that I have 160 sex offenders in my county. Multiple rapists, sexual battery offenders, but most alarming, child offenders. There are two living in our apartment complex that have been charged with child pornography, and several more child offenders in surrounding neighborhoods.
Look up your sex offender registry, look at the charges, look up their addresses, memorize their faces. Know who to watch out for.