At the micros it's all about extracting value from your good hands against fish, and avoid playing too much with regs unless you think you can outplay them. The big money will come from fish.
So quickly try and determine who is a fish. If you have a HUD, you can be pretty sure that players with a VPIP of over 40% are probably fish, or if it looks like they are playing a lot of hands in general. Limping, buying in for the table minimum, and min bets postflop are also signs of a fish.
For me it depends on the type of the fish. I think we could generalize two main fish types:
=> passive
=> aggressive
When playing against the first ones they would probably like to see cheap flops and rather call bets than raise. Here, we should eliminate our bluffing to minimum and get max value with our value hands. I am usually don't scared to get 3 streets of value with a hand as weak as top pair, good kicker. Contrary, against good players, i go for one, maximum two streets of value with that particular hand, but of course it is also player [ and board] dependant.
When playing against aggressive fishes, I would try to find the perfect spot to trap them. I won't go in big pots against them unless I have The Nutz or pretty close to the nutz ( sets, straights, flushes, full houses).
This is a very good point, not all fish are equal. You basically have to ask yourself if this particular fish is going to make more calling mistakes (against calling stations, you should bet big with your good hands) or if they will make more betting mistakes (against maniacs/aggro fish, you should trap and in some cases be prepared to call down lighter than usual).
Also something VERY important to understand is that fish don't fold straights, flushes or full houses. Even semi-good players can't let go of a full house most times. Taking this into consideration will help your winrate a lot.
This is from a hand I played today:
6 handed, a fish limps UTG. It folds to me in the BB, and I raise it up with KTo.
After check-calling flop, and leading turn, I get him to hang on to the river. The board is TKTTJ. What is the best thing to do with four of a kind in this situation?
SHOVE.
Some people might bet small here because they are afraid to scare the opponent away. I shoved 4.20$ into a 1.76$ pot and got called by JJ. I would have gotten called by any Kx hand too, and probably all Jx. AQ for a straight probably would have called too. If he had air, he would have folded anyway, so going for max value is the way to go.
These spots are rare (you don't get four of a kind or a fullhouse very often), but when they occur, trying to get it all-in against straights, flushes and full houses that can't fold is sure going to increase your
bankroll by a lot in the long run.