Some players have the automated reaction to bluff frequently, and that is not recommended. They should just pay attention to the table ad maybe even feel it a little bit before they decide to bluff. Keep in mind that the other players are probably looking themselves for an occasion to bluff. You can tell sometimes when they are bluffing, and the same way they can tell it too sometimes when you are tring to bluff. It does work when nobody notices, but if they do it will only cost you money. So, use it wisely and only after you get some experience.
For reference and help, take a look at these situations when you must not, under any circumstances, bluff.
1.When it is obvious that you will.
If the players know you and know your stille, they can tell when you are bluffing in some situations. Dont make this mistake because you would give them free money this way.
2.When you just bluffed and they caught you.
If you are already labeled by the rest of the players as a poor bluffer, you should let them forget about that and only then try it again, hoping this time you can do it right.
3.When you are faced with a dangerous flop.
Look...