Whatever actions you take in a hand tells
a story about what you're holding. If you're playing 6max NLHE and raise preflop utg to 3.5xBB, you're representing a set of hands. On the flop, you cbet, check/call, check/fold, or check/raise - each of those actions represents a narrower set of hands relative to the board. On the turn, you again cbet, c/c, c/f, or c/r, which again narrows the set of hands you're representing. Etc.
Here are a couple of thoughts on bluffing -
1. You're telling a story. If the person you're telling it to isn't listening, don't try it. This is one of the major reasons you shouldn't bluff much at microstakes, most people aren't listening.
2. Some people do listen, but they aren't the right people to bluff, cuz they have a clue as to what you're doing, or cuz they want to gamble.
3. Identify people at your table as someone who can or cannot be bluffed off a hand before you try bluffing.
4. Make sure the story you're telling is coherent. I constantly call people on bluffs that don't make any sense (which occasionally causes me some problems at microstakes). My favorite is an oop pf raiser who checks a dry A hi flop, checks a blank turn, and then bets on a rivered A - that bet never makes any sense, the A shouldn't have helped him.
5. Semi-bluffing is far superior to pure bluffing, since by the time you showdown (if you get there), you may actually have a hand.
6. Bluffing is overrated at microstakes by many players. Most micro players make huge mistakes without you needing to bluff them, and many of them can't be bluffed anyhow.
An example of a good bluff:
You're on the button and CO has shown a tendency to give up if he doesn't hit the board fairly hard. You're dealt 87s, CO opens for 3.5xBB, you call in position, blinds fold. Flop is 972r, giving you middle pair and a backdoor flush draw. CO cbets 2/3 pot - what's he got? Well, if you know he cbets 100% of the time, all you know is his range for opening from CO - let's say he's basically got alot of medium/large Ax's, some broadway cards, some suited connectors, and pocket pairs. Did the flop help him? It certainly helped 22/77/99, but really didn't help any other hands. If he's got TT+, he won't care that the board didn't help, but all other hands are now drawing. So what do we do w our middle pair? Call. Turn is an A, and CO checks. Why did he check? He could be tricky here w Ax, but chances are he's checking cuz an overcard just hit the board. Let's say the A gives us a fd and middle pair - this is a beautiful spot to semi-bluff. Since we know CO gives up without a good hand, if he calls, we're not continuing on the river without our hand improving to at least 2 pair. If he raises us on the turn, we're also folding. Otherwise, we just bluffed him off a hand.
This is called floating, though floating doesn't require us to have any hand at all, just two cards. If we know he'll fold without making a hand, we can bet the turn behind his check representing a strong hand and be confident that he'll show us his hand by either folding or by calling/raising, and it doesn't matter whether we're semibluffing or holding 62o.