15 December 2011
Not all casinos offer this option, but in casinos that do allow it, you have the option of giving up without playing your hand at the cost of half of your original bet. You would only consider surrendering a hand that had almost no hope of beating the dealer, since this bet, by its very nature, is almost always a negative expectation option.
There are two kinds of surrender options. Early surrender is when surrendering is allowed before the dealer checks his hole card for a natural. This is the more advantageous option for a blackjack player because you can sometimes save half your wager if the dealer has a blackjack.
Late surrender is when you're allowed to surrender, but only AFTER the dealer checks his hole card for a natural. This is not as good an option as the early surrender option.
To signal the dealer that you surrender, just tell him that you give up.
Hands that total 12 through 16 that don't have an ace in them are considered stiff hands. That means they're likely to bust or be beaten by the dealer. These are typically the only kinds of hands you'll surrender, and you won't always surrender these either. Basic strategy will give you guidelines as to whether or not you should surrender.