The bluff is an important weapon for the winning players, but not addictive. It should be used in accordance with precise rules, so always be unpredictable and minimize the risk of being discovered ....
Less strong are the opponents, the harder it is a bluff to succeed. A strong player tends to respect the episodes of his opponents and has the discipline to throw away his cards, a weak player, however, tends to go to see much more than necessary ... and maybe not because he understood that there implement a bluff, but out of simple curiosity, because you never know, because he does not want to sleep with doubt about what you had. In other words, nothing moves fine against those who can not understand.
The position at the table is important and in general it is best to speak after the opponents because you have more information and we can adjust accordingly. But bluffing does not mean that this rule always applies, especially against very experienced players. Bluffing after checking opponent may in fact be more dangerous than talking to him first, because those who did check has shown weakness and may suspect that this is precisely the reason the bluff ... and then gets some more temptation to see.
The more players we have in hand, the harder it is a bluff to succeed.
Players tend to be more cautious when the average number of chips rather than when they are short or big stack: So in those conditions are more likely to be bluffed and they themselves tend to do less.
The bluff is normally at the end of the hand, when all the cards are already on the table: there is no hope of winning the showdown and bluffs as the only way to win the pot, that pretends to have a stronger hand than is reality.
In all styles of poker is harder to bluff if you play Limit, Pot Limit or rather than No Limit. The reason is intuitive: Limit playing the relationship bet / pot is very low and therefore it is easier for opponents to have adequate opportunity to go and see with their hand.