Card Counting for Trick Games
Card counting in trick games has nothing to do with casinos. It just means remembering what has been played, and it's the single skill that separates good players from average ones.

Start with trumps
Count the trumps as they fall. When none are left with the opponents, your side-suit winners are safe.
Track voids
When someone can't follow suit, they're out of it. Remember it; it tells you who can cut that suit later.
Know the boss card
The highest card still out in each suit. In 28 and 29 that's the Jack, then the 9; in Call Break, the Ace, then the King.
Count points (in point games)
In 28, 29 and 304, add up the points your team has taken and what's left. You'll know when the bid is safe or lost.
Practise
Cheettukali's computer players remember played cards and voids. Watch what they play and try to predict it; it's great practice.
FAQ
Is card counting allowed in card games?
Yes, in home and online trick-taking games remembering cards is simply good play.