As soon as all the players are given two cards, the dealer will ask you, if you want another card. If you wish to receive more cards, depending on which cards are already dealt, you can do do one of the following:
Stand:
this is a signal to showing you think you should not draw anymore cards. To signal the dealer a player wishs to stand, he waves his hand as if waving the dealer away. When playing with a single deck of cards, signaling to standing is done by putting the cards faced-down under the bet.
Hit:
When you wish to be dealt another card you signal to hit. You may hit as long as you want until you decide to stand or you bust. To signal the dealer to hit you, flap you finger on the table. When playing with a single deck of cards, you should rub your cards with ease on the table.
Double:
you can decide to double your bet if you feel you need just another card to win. You can only use this option with the first 2 cards. There are some casinos that limit this option to hands totaling 9, 10 or 11. To signal a double, you put another bet next to the original equaling to it. When playing with a single deck, put your cards facing upwards next to your bet.
Split:
you are allowed to split your hand to two hands, if the first two cards have the same value. After splitting, each card from the original hand is the first of the new hand. You are required to bet for the new hand as well, the same amount you bet on the first hand. You may split the hand again if you can. Doubling after splitting is not always permitted. If you wish to signal a split, put another bet, equaling to the original, next to it.
Surrender:
this option is not allwed in all casinos. If you decide it will be impossible for you to beat the dealers hand, you can declare surrender. Then you will automatically lose half of your money, but save the other half. Usually you are offered to surrender after the dealer checks if he has blackjack, this is called late surrender. Sometimes you must declare surrender before the dealer tends to the first hand.
Online Blackjack:
in online casinos, to signal any of the options you should only press the according button. For example, if you wish not to be dealt another card, press the stand button.
As soon as all the players have finished their playes, the dealer plays. The dealer can only stand or hit, and this is always controlled by strict rules. Usually the rules are that if the house gets less or equal to 16 the dealer must hit, and if he gets 17 or more he must stand.
After the hand of the dealer is done, he tends to the bets, paying, collecting and pushing ties. This is the end of the round, and a new round starts.
Rules
Bets in blackjack are placed before the first card has been dealt. The payout rate for a player who beats the dealer is even money (the amount paid is the amount bet), unless the winner has a blackjack in which case the rate is 2:3 (9 dollars paid for a 6 dollar bet).
When splitting aces, you can only play one of the aces as a new hand. If you get a ten-value card after an ace aplit, it is not considered a blackjack. Although these hands beat a hand of less than 21, they will lose to a blackjack. Also they pay the normal rate of even money, and not 2:3.
Insurance Bets:
This side-bet is offered when the dealers draws an ace for his first card (the dealers first cards also known as face card, since it is facing up). The bet is over the dealers second card, if he pulls a ten-worth card, thus getting a blackjack, the bet is won. When you bet an insurance bet you wager the same amount as your original bet, and get a 2:1 payout rate. This has nothing to do with your original bet or hand, you still have to better the house, but if the dealer does draw a ten-worth card you can only tie with another blackjack. After the dealer checks with all the players if they wish to place an insurance bet, the dealer exposes the second cards value. The losing insurance bets are collected on the spot, and the round goes on normally.