Ten life lessons to excel in 30's

1. Start saving for retirement now, not later. Ideally the amount should be between 30-40% income, after providing certain amount for emergencies. Don’t spend frivolously. Don’t invest in anything you don’t understand. Don’t trust brokers.
2. Start taking care of health now, not later. Simply put eat better, sleep better and exercise more.
3. Don't spend time with people who don't treat you well. Don’t tolerate people who don’t treat you well. Don’t tolerate them for financial reasons. Don’t tolerate them for emotional reasons. Don’t tolerate them for the children’s sake or for convenience sake. Don’t settle for mediocre friends, jobs, love, relationships and life. Stay away from miserable people. Selfishness and self-interest are two different things. Sometimes you have to be cruel to be kind.
4. Be good to people you care about. Show up with and for your friends. You matter, and your presence matters. Tragedy happens in everyone’s life, everyone’s circle of family and friends. Be the person that others can count on when it does.
5. You can't have everything; focus on doing a few things really well. Everything in life is a trade-off. You give up one thing to get another and you can’t have it all. It takes a lot of sacrifice to achieve anything special in life. 
6. Don't be afraid of taking risks, you can still change. 
7. You must continue to grow and develop yourself. If you’re one of the few who continues to educate themselves, evolve their thinking and take care of their mental and physical health, you will be light-years ahead by 40. Warren Buffett once said, the greatest investment a young person can make is in their own education, in their own mind. Because money comes and goes. Relationships come and go. But what you learn once stays with you forever. The number one goal should be to try to become a better person, partner, parent, friend, colleague etc. In other words to grow as an individual.
8. No body knows what they are doing, get used to it.  You cannot anticipate your life five years into the future. It will not develop as you expect. Stop assuming you can plan far ahead. You cannot lose what you never had. Most feelings of loss are in your mind anyway – few matter in the long term. Sorrow is part of everyone’s lifetime. Be kind to yourself and others.
9. Invest in your family; It is worth it. Spend more time with your folks. Everyone gets old. Everyone dies. Take advantage of the time you have left to set things right and enjoy your family. You’re too old to blame your parents for any of your own short-comings now. All preconceived notions about what a married life is like were wrong, especially once you have kids. Marriage is worth it, if you had a healthy relationship with the right person. If not, you should run the other way. Try to stay open to the experience and fluid as a person; your marriage is worth it, and your happiness seems as much tied to your ability to change and adapt as anything else. Children are the most fulfilling, challenging, and exhausting endeavor anyone can ever undertake.
10. Be kind to yourself, respect yourself. Be a little selfish and do something for yourself every day, something different once a month and something spectacular every year.