See also Single Table Sit'n Go Strategy (Part I)
In the middle of the game.
The middle stage of the game comprises of the 4th-6th blind stages. When the game reaches this stage, about 6-7 players are left at the table. The number may vary, as some games go on for a long time.
This is the most crucial stage of the game. Blinds put a lot of pressure on the players. You will have to get aggressive at this stage, if you wish to build a substantial amount of stack for the later part of the game.
Building a sizeable stack.
One of the guaranteed ways to build a sizeable stack is to bluff intelligently. A keen player will have already scanned each player in the early stage of the game to conclude whom to avoid and whom to trap.
Suppose you possess 89 of clubs in the big blind. You have folded to the small blind. Now, your wit will tell you that this player is an amateur and, in the early stage, had folded on the flop to bets. The flop is 6-10-3 with one club. If this player checks, you should bet. Since this player is a passive one, there is every chance that he or she will fold. If he or she does not, you still possess a gut shot draw and a backdoor flush draw.
Suppose that the player calls your bet. The turn gives a Q, not a club, and he or she checks one more time. When the player does that, you have two choices: either place him or her on a straight draw, or put a low pair. He or she is a passive
player, so, you should have no problem betting out again. The passive player will likely fold with a pot size bet. If he or she calls your bet, you will have to lend him or her credit for a hand. Also, it is wise to check/told the river, if you don't improve your game.
Making a continuation bet.
Here is another smart strategy: make a continuation bet. (This is unlike the example of the early stage game, where you could check or fold AK during a had flop).
Let us say you get the same hand. AK. You raise a 3x the big blind and get a call. The flop comes 642 and, at the same time, the big blind checks. There is a high chance that your opponent possesses a big unpaired hand such as KQ. At this stage, you cannot afford to be conservative, as the blinds are increasing and it is necessary that you build a stack. What to do now? Well, you must throw a pot size bet. If someone calls it, check or fold the remaining of your hand, if you do not improve your hand.