Invest Often

Make investing part of your routine.  Instead of waiting until you have lots of money saved (which almost never happens), start investing a small amount each week, each paycheck or even each day.  You can find lots of programs from companies that allow you to invest small amounts of money each week in their stock or mutual funds without charging any transaction fees.  Invest as often as you can.  Don't just think about investing at the end of each year or during tax time.  Make it a part of your thinking each time you make a money decision.  Think about giving up that $2 cup of coffee and putting the money in your savings account.  If you have a 401K or other plan through your job, take advantage of it.  The money will barely creep in at first, but once it starts growing it just keeps growing and compounding faster and faster.