The Red Seven Card Counting system
The Red Seven system relies on a running count to tell you when the odds favor the player. The running count is simply a number. You must keep this number in your head. For every card you see that is then discarded, you add or subtract its value from the running count. This running count tracks the history of the game.
The Red Seven Count is an unbalanced count. That means if you start from running count of zero and count through a single deck you will not wind up back at zero. In fact, with a single deck you will wind up a +2. A balanced method on the other hand will wind up at a zero. The benefit of the unbalanced system is that you only need to remember the running count. You do not need to calculate a true count from the running count.
In order to compensate for the unbalanced count, unbalanced systems use an "initial running count" or IRC. That way, when you count through the deck starting at the IRC you will get zero. In addition, zero is the pivot point, meaning that a positive count (above zero) indicates a players advantage.
For the Red Seven system, the IRC is 2 x the number of decks. So, the IRC is defined by the table here. The Red Seven system has an easy to remember IRC.
Number of Decks 
IRC 
1 
2 
2 
4 
6 
12 
8 
16 
Each card you see on the table (and is then discarded) is translated into a value and added to the running count. The values assigned to the cards are demonstrated in this table.
Face 
Value 
2 
+1 
3 
+1 
4 
+1 
5 
+1 
6 
+1 
red 7 
+1 
black 7 
0 


Face 
Value 
8 
0 
9 
0 
10 
1 
Jack 
1 
Queen 
1 
King 
1 
Ace 
1 

Note the value of the seven card. A red seven is counted as plus one. These are seven of diamonds and seven of hearts. Black sevens are value zero. These are the clubs and spades. By splitting the value of the seven cards, the system becomes unbalanced.
For example, let's say you are counting into a six deck shoe. The Initial Running Count (IRC) is 6 x 2. That means the IRC is 12. Now, imagine you see the cards being dealt. You translate each card into it's value, and then add that amount to the running total. When you have a high running count number, there are more ten cards in the shoe. At this point you realize that the odds are in your favor.
It is generally recommended that you practice counting in pairs of cards. When you look at several cards at once, you can quickly cancel out a pair consisting of one low card and one high card.
Pair 
Total KOCount Value 
King, 8 
1 
8, 4 
+1 
5, 2 
+2 
Ace, Jack 
2 
All card counting system rely on knowing when the odds shift from the house to player. As we’ve seen, by careful counting you can maintain a running count of the ratio of high to low cards in the shoe. The next part is taking advantage of the shifting odds. You take advantage of the odds by increasing your bet when the odds are in your favor. You wager more when you have a better chance of beating the house.
Our game uses a simple two wager scenario. A low bet, usually the table minimum. You use the low bet on a new deck, after the dealer shuffles or when the running count is not in your favor. The second bet is the high bet. This should 10 times the low bet. So, if you are playing a $25 low bet, the high bet would be $250. The high bet should be no more than 2% of your bankroll.
The "key point" or "pivot point" is the critical point at which you should switch between the low and high wager. Another easy feature of the Red Seven Count is that the when using the proper IRC, the pivot point is zero. Thus any positive count indicates a player advantage. The higher the positive count the higher the advantage.
Note: Many blackjack systems wager according to the value of the count. So, you'd wager more on a +3 count than a +1. I prefer a simple system with only a high and low wager, but you can vary the high bet based on the count.
That is the basic Red Seven system. Since it is unbalanced, you do not need to calculate the true count. All you must know are the point values and the IRC.