For the 20 something year old.

A couple of things i found interesting reading this article:
1) not making a choice is a choice.  Tim's mentioned that before though I can't remember what context it was in.  When we dont know what to do and just sit around doing nothing till we know what to do, that in itself is a choice.  Even choosing not to choose is a choice.
" 'These 20-somethings think they are keeping their options open, but they are actually closing doors.' Resumes start look thin, their peers begin surpassing them and they may get stuck in underemployment."

2) Learn how to have healthy relationships.  Date people who you can see yourself being with long-term and not put it off till you think you're "old enough". Love is still just as important in your 20s.

3) apparently more than half of all marriages are preceded by cohabitation. things get messy when people dont communicate their expectations of cohabitation and its significance.. then as Nigel says, "it's easier to stay in a bad relationship than to get out of it." 
"cohabitation can lead to marriages that aren't compatible because it becomes so difficult to untangle."

http://www.forbes.com/pictures/fijj45emk/how-you-spend-your-20s-will-define-you/