There are several factors that combine to determine how successful a bluff is going to be. We all know about player numbers and that is rather obvious because the more opponents that you have then the lesser your chances are of bluffing. However let us look at a heads up situation exclusively and take it from there. Firstly I think the size of your bet carries more influence than any other with regards to being able to bluff successfully. For example let us say that you were playing NL100 and the pot was $20.
If you bet $1 into a $20 pot then you are not only offering your opponent pot odds of 21/1 allowing them to call with most hands but your bet looks suspicious. Many players will bluff raise you out of principle in these situations. So while this is an extreme example and no serious player would bet $1 into a $20 pot then it still highlights that bet sizing if got chronically wrong impacts your ability to be able to bluff. There are certain bet sizes in poker that cannot possibly be correct and betting $1 into a $20 pot is one of them.
If you have either end of the spectrum of your range then the bet sizing still doesn’t make sense. If you have a strong hand then you can bet more than $1 if you feel that your opponent can call. If they will call $1 then they will call $2 and $3 and so on and so on which means betting $1 is silly if you have a strong hand. If you feel that your opponent cannot possibly call at all then betting $1 is wrong and you should check. Whichever way you look at it then betting $1 is wrong and if you are bluffing then offering crazy pot odds is not the way to make that happen.
So bet sizing is important but then again so is your opponents hand range. If you were the pre-flop raiser and the big blind called with the flop coming 10-6-2 rainbow then the combined width of your opponents range and the flop texture make it unlikely that your opponent has a hand that can call a c-bet. So the chances of your opponent calling or raising are a huge factor in bluffing and doing it successfully.
A simple example could be if your opponent open raised from the UTG position in a full ring game and the flop came A-K-4 rainbow and you had called on the button with the 10s-9s. Your opponent will have a narrow range from UTG and so when they c-bet on this board then bluff raising would be a bad move. On your lucky days then you may find your opponent with a hand like Q-Q or J-J but mostly they will have hands that they will not fold like A-A, K-K, A-Ks, A-K, A-Qs, A-Q and A-Js.
So the chances that your opponent will fold to a bluff are connected to the board texture and their range. Also if you have a very aggressive history then your chances of bluffing your opponent are going to be much less. If it has been folded around to you on the button and you have been raising liberally then any semi-competent player is going to recognise that and do something about it.
So your history also has a big impact on your chances of bluffing and your opponent may decide to call with a strong range and let you lose some more money post flop. Like for example if they call with A-Q and the board is A-10-5. While this example doesn’t really fit, what does fit better is if the board is 10-5-2. In this instance your opponent could check-raise you on the flop or check-call and look to take the pot down on the turn.