There are two strategies that you can use to add shares to your investment portfolio. One strategy is to use what is known as "dollar-cost averaging", and the other approach is the "buy low-sell high" strategy.

The "dollar cost average" strategy entails that you invest a fixed amount of money in the market at a pre-determined time. Perhaps you decide that you can afford to invest $50 a month in the market. You do this regardless of whether the market is high or low, bearish or bullish. You just continue to invest the same amount of money month after month. If prices are low, your $50 investment will buy you more shares. When the market is high, your $50 investment will buy you less shares. For example, let's say that you decided to invest your money in a stock that is currently selling for $25 a share. That means that your $50 investment will buy you only 2 shares of stock you have decided to invest your money in. Let's say that a month later, due to widespread "panic selling" of stock overall, your stock falls to $5 a share. What that means for you is that you are now able to buy more shares of your chosen stock than you were able to purchase in the previous month. Instead of buying only 2 shares of stock for $50, your $50 investment now is able to purchase 10 shares (8 shares more than before). When the price of a stock rises in value, your investment buys less. When the price of a stock falls in value, you are able to buy more. When all is said and done, you pay the average cost of what your stock is worth; hence the term "dollar cost averaging".

The other way of adding shares to your portfolio is known as "buying low and selling high". Unlike "dollar cost averaging" you don't invest a certain amount of money at a regular interval. What you do instead is that you wait on the sidelines for your prey to appear. Once your prey-the lowest possible or right price--appears you pounce on it by injecting large amounts of money in it a la Buffet style. To return to our prior example: Instead of paying $25 for two shares of your chosen stock as in the prior instance, you wait until it drops to $5 and then and only then make your purchase of 20 shares! That way you get more bang for your buck.

Let's compare: When you used "dollar cost average", you were able only to purchase 12 shares of your chosen stocks with your $50 investment spread over a 2-month period. In first month, you bought two shares for $25 each. In the second month, you were able to purchase 10 shares at $5 a share. All told, you were able to buy only 12 shares in all. In contrast, when you used the "buy-low and sell-high" investment strategy, you were able to purchase 20 shares in that same time period-10 shares for $5 dollars in the first month, and the same amount of shares in the following month for the same price. All that enabled you to purchase 20 shares at $5 a share. In other words, by paying the average cost of your stock, you pay more and buy less, but by paying a low price for your stock, you pay less and buy more. Put differently, when you pay more, you earn less. When you pay less, you, in effect, earn more. In still other words, the return on your money in the long run will be greater in the latter instance than in the former one.

Which strategy should you use? It all depends what end you want to achieve. If you want the greatest bang for your buck and you don't mind waiting for the right time to invest your money, you might want to use the "buy-low and sell-high" investment strategy. On the other hand, if are in a hurry to invest your money, but don't mind an average return on some stocks in your portfolio, then you might want to use the "dollar-cost averaging" investment strategy. Or, perhaps, you just might want to use a hybrid approach by using both investment strategies.

To summarize, the two investment strategies for adding more shares to your investment portfolio are "dollar cost averaging" and "buy low-sell high". The former strategy will result in your paying more for less and the latter strategy will result in your paying less for more. In the former instance, you will receive a lesser return on your money than in the latter instance in the long run.