I typically buy the QQQs when they are low. The lower the better. Then, I sell them when they are much higher.
You buy and sell them using the same setups you trade in any other instument. You just lower your expectations up your shares. Take a free trial on Tradingmarkets.com and read some of Don Millers articles. He'll give you some specific setups.
Vishnu, I typically buy the QQQs when they are low...Then, I sell them when they are much higher. LOL BTW, an equally good strategy is to short them when they're high, then cover them when they're much lower...