This depends on which put you purcahse and if you sell calls to offset the put price which is what many professionals do. This is called a collar.
As the QQQQ index is at roughly $44 this means it protects $4,400 worht of portfolio. I would maybe pick an index like the MNX instead that is trading for $177. One put protects $17,700 in stock, so you will only need 5 or 6 puts instead of 23 contracts of the QQQQ.
Then simply pick something out of the money depending on how much protection you want. The put will be exspensive which is why most people sell calls (the collar). because of margin you will have to sell the call in the stock instead of the index.
You may want to buy a book on this and get caught up.
As the QQQQ index is at roughly $44 this means it protects $4,400 worht of portfolio. I would maybe pick an index like the MNX instead that is trading for $177. One put protects $17,700 in stock, so you will only need 5 or 6 puts instead of 23 contracts of the QQQQ.
Then simply pick something out of the money depending on how much protection you want. The put will be exspensive which is why most people sell calls (the collar). because of margin you will have to sell the call in the stock instead of the index.
You may want to buy a book on this and get caught up.