Soooo, since i wrote a whole ton on this and i don't want to write it again i will copy pasta my blackjack tips, and i am glad to answer questions:
Well there is what is called Basic Strategy and it is basic guidelines you generally follow except under basic circumstances for example if you don't know what the count is and you have 16 and the dealer is showing a seven, you hit statically you will come out winning more frequently than staying on 16. Many casinos will only allow to double down on ten or eleven. When you double down you must be on your first two cards and you are saying you will take one more card and double your bet. You can "double for less" meaning you increase your bet by any amount less than your original bet.
There are things which are wise to split no matter what like always splitting aces and eights starting separate hands. It is generally a bad idea to split tens but when counting cards but when it is a high count it is a good idea to split to a dealers 5 or 6.
If you are decent at counting cards your strategy changes. If the dealer is showing a five or a six and your hand is 7 (a three and a four for example) but you know the deck is hot (more high cards than low card) you would double down because the dealer has a high probability of busting since his other card is likely a ten and he is very likely to get another.
There is also something called insurance, when the dealer shows an ace as his up card you are offered insurance where you bet that the down card is a value of ten, if the down card is not a ten you lose your insurance and the hand plays out as usual. If you are dealt a blackjack when the dealer shows an ace you can take even money or hold out saying the dealer doesn't have it, if he does you don't win anything. Insurance is usually a way to spot people who aren't experienced gamblers, unless you are counting cards insurance is ALWAYS a bad idea. If it is a hot deck (particularly on single deck games) there is an increased probability of a blackjack and therefore you might take insurance to hedge your previous bet.
This is all very basic stuff more advanced stuff requires some math >.>
and my second reply in the same thread
A pen and paper is pretty useless in counting cards just so you know...
Counting cards doesn't improve the amount of hands you win by a great deal it only reflects the value of cards remaining to be played. An often overlooked aspect of card counting is that when you have a higher probability to get a blackjack the dealer does as well. For this reason basic strategy is vital. A very very basic counting system called a Running Count or a High Low system is very easy to master, cards 2, 3, 4, 5, and 6 (these cards are called bandits) are given a value of plus one 7, 8, 9, are given a value of zero while 10's and 11's (aces) have a value of negative one; so, if you start with a full deck you would start on zero and end at zero.
So, say you are playing blackjack at a table with a single deck (pretty popular in Vegas) you have been taking the small bleed for fourty minutes (betting the table minimum) at two dollars a hand, if you follow basic strategy you should be just slightly under even. Now assume it is just you and the dealer, and finally you get a hot deck, half the deck is gone and the count is plus five (five more tens than bandits) you lay down fifty bucks and get a 20 while the dealer is showing a seven, the count is now plus three you split tens to the dealers seven given that you have a strong chance of getting a better card and a high probability of the dealer standing on 17 (dealers have to stand on 17 unless it is soft 17). One hand gets an ace (blackjack) and the other and eight the dealer flips a ten and you have just won 125 dollars. About now is when you change tables, pit bosses keep track of your wins and losses but they really don't like it when you win consistently at a single table and you don't typically want to stay in a casino more than an hour and half. Card counting is not a long haul game, it is a hit and RUN game. Over long term, card counting only increases your sustainable winnings by about two percent, long term play at a table with basic strategy that leaves your optimum chances at about 53% so it isn't like counting helps you win, it tells you when you are most likely to get dealt a winning hand.
I should also note that is a very simple counting system and while it can help to some degree more advanced systems are going to help a lot more, at the very least a High Low counter should keep track of how many aces have been dealt. The movie mentioned earlier 21 is based on a book titled Bringing Down The House which was advertised as non fiction even though many of the characters and events were fictional. Although it is true that MIT students did make a fair deal of money on the Vegas strip, the teacher ring leader, and pit bosses stealing chips, and strippers cashing chips is not factual. There seems to be this myth about counting having something to do with being good with numbers and television perpetuates it. Card counting is a memory and association game Edward Thorpe, a mathematician set up the system seen in the movie 21 His system was very complex and difficult to learn given that virtually every given card had a different value. In the movie Rain Man the player is able to beat the casino because he is a savant (meaning he has absolute memory recall) so he could always say how many of any card was left in the deck.
If you are serious about wanting to play blackjack i am a big proponent of the Omega II counting system Which is: (1,2)+1 (5,6)+2 (7)+1 (8)0 (9)?1 (10)?2 (11)0 but unless you know how card counting affects basic strategy and probability it is pointless, so get some books and some cards and practice A LOT and i'm not talking an hour or ten hours i'm talking like forty hours before you even try playing at a casino and you will still lose for quite some time until it becomes second nature.