There's a wide range of strategies to employ when building a well-diversified portfolio. Where you are in life, including age and proximity to financial goals, will determine which strategy is best for you. Eric Tyson,MBA, offers some sample strategies in Mutual Funds for Dummies (Hungry Minds; $21.99).
If you're in your 40s and looking to put as much money away as possible for retirement, Tyson suggests structuring a portfolio similar to the following:
If, however, you're about 10 years older or nearing retirement and just want to keep your investments more fixed, you might consider the following breakdown from the tax-friendly Vanguard fund mix: