Most professional players would agree that aggression is good. Most players go through stages as they learn and become better players. We mostly start as Fish. Please behind to Fish, at lower stakes they keep it going. Some start as a NIT, playing super tight and betting only when they have a great hand. Avoid them. Most players graduate to being a LAG (loose aggressive). They discover the value of aggression and win by making other players fold. But they still play too many hands. The next stage is the TAG (Tight aggressive). They remain aggressive but tighten up their ranges.
When you move up in stakes, first the Fish and NITs become scarce and you are playing against a LAG or a TAG. Larger stake games are far more aggressive. This requires new strategies. You must become comfortable with aggression.
LAGs are the easiest to exploit because they play too many hands. An opponent that starts with too many hands has to get rid of the weaker hands somewhere along the way and before showdown. They get rid of their hands by either folding or getting you to fold.
If your opponent likely has a strong hand, fold. It might be fun bluff catching but it can be very expensive. You need to have fun winning, not playing games. You win by calling bluffs when it is appropriate.
Know your opponent. Learn to evaluate the board. Learn how to estimate his probable hands. Use that knowledge to call bluffs. If your opponent may have one of a dozen hands, but only 2 of them will beat your then then call or raise. If he makes a habit of bluffing too much then call every time.
Get out of the way of opponents that play mostly strong hands. Call the bluffs of players that play too many weak hands.
One example is the opponent that C-Bets too much. Some will C-bet nearly 100% of the time and are easily exploitable just by calling all of their C-Bets.
What I touched on earlier is one of the biggest mistakes that new players make. They do things for “fun”. If you find someone who has fun catching bluffs, patiently wait for him to call yours when it's not a bluff. Occasionally show him your cards when you have a successful bluff.
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