I guess, having just turned 40, I am one of the oldest on this forum. I have been married nigh on 12 years, have five children, and have worked constantly since leaving school at 16 years of age. A few tips from me.
# Tip for a successful marriage - Compromise
# Tip for a successful marriage - Remember that a 'fact' can be completely different from where you perceive it from.
Where You Are Depends on How You Look at Things - Lifehack.org
# Read 'Automatic Millionaire' ( and A.I. Homeowner) by David Bach, as early in your life as you can.
# Implement GTD now.
# Learn to just be neutral on things you might disagree with that dont really impact on you, especially when dealing with siblings. When siblings quarrel, they tend to excel in it.
# Throw off the yokes of alcohol, drugs, coffee, tobacco immediately. The younger the do it, the less of an impact these will have in your life, and the easier they will be to leave behind.
# Give up work as an 'employee' as soon as you can, and work for yourself.
# Make Personal Development an every day part of your life