Before You're 30

In less than a month I'll be hitting my 27th birthday.

Last week I came across this article by Jason Boyett at Relevant Magazine's website.  9 Things To Know Before You're 30.

I read through the list and had to smile.  Some of those lessons I wish I'd learned in my early twenties.  For one or two I'm still paying the price-tag of the lesson.  And some, to me, seem to just be slowly coming naturally as I'm open to God working in my life and as I'm growing and changing as a person as well.

My question is this - what lessons do you wish you had learned earlier?  is it one on the list, or something totally different?  what's the best lesson you've learned?