BOSTON (TheStreet) -- There's a Seinfeld episode in which George Costanza decides to do the exact opposite of what his instincts tell him, and suddenly his entire life improves. His character does not generally tend make the best choices, so the premise for him to do the opposite of what he normally would is a good one.
That same may hold true for many of us when we invest for retirement. The classic example is "buy low, sell high" -- our tendency may be to chase the latest stock or invest when a particular asset class is having a good run, when the best choice may be to do the opposite.
When it comes to saving for retirement, it may be helpful to view a list of what not to invest in, then find a better alternative:
I suspect George would buy Apple (AAPL) stock right around now (or gold, silver or oil). Whether a stock is priced correctly or not, it's important to remember that the price of any one stock could fluctuate dramatically in a short period. There is company risk (what happens if Steve Jobs resigns?), market risk and economic risk, to name a few. It's best to avoid investing your retirement savings in individual stocks and instead choose a low-cost mutual fund or ETF, such as the iShares S &P 500 Index (IVV) , that follows the index of the asset class in which you would like to invest.
Leveraged or inverse mutual funds or ETFs
This is an investment George would jump on the moment he had a chance because of its promise of returns two or three times that of the market. Leveraged funds use futures and options to try to amplify returns and rely on "borrowed" money to increase their bet and therefore their potential gains. But the potential for losses is also significantly higher (and they sometimes move in the opposite direction you think they would, like George). While there might be a time and a place for leveraged funds, one should proceed with caution and due diligence. Certainly for first-time investors starting off with little to no retirement savings, leveraged funds may not be the first place to invest.