That title may seem a little strange, but it’s because my tip is a little hard to describe. What I’m asking you to do as a designer is to make sure that one player’s turn is not the same as another player’s turn.
The Problem
Many games seek to be fair, and a common way to do that is to make sure everybody has access to the same options on their turn. For example, in Dominion, every player has the option to buy any card on their turn. There’s no shifting market and there’s enough of every card that you’re not going to run out soon. However, this leads to a problem. If the first player on their first turn buys card A, then ends their turn, what is the next player going to do? Well, if they assume that the first player is good at the game, they might also buy card A. And so might the next player. If it’s correct for one player, then it will probably be correct for every player, at least if they don’t have a personal bias or are purposefully trying to make it more interesting. If this happens in dominion, you might get to the point where everyone’s decks are basically the same and players feel like the only reason they won or lost was randomness, which isn’t great.
A similar issue is in a game like Five Tribes or other games with shared boards and pieces. A player may spend several minutes looking at the board, doing analysis in their head (they can’t say it out loud), then come to a decision about the best course of action. Meanwhile their opponent has been doing the exact same mental calculus and likely come to the same conclusion. Now, that player also needs to do it, from scratch, for their turn. If they had more things to distinguish between them, then the second player could have been doing things unrelated and saved everyone some time.
Solution 1: Player Powers
Since this problem is most egregious in the early part of the game, you need to make the solution appear just as early. A common way to make sure players start off the game in different enough positions to make different decisions is to grant them some type of player power. This can be a constant one, like making a certain resource always sell for some higher amount, making it more likely they’ll take that type, or a one-time ability, like doubling all their red resources, meaning they need to start the game with a plan to use it later. Player powers are a little controversial with some designers, though, since they force the game into a new state without letting the players adjust, and they are also really hard to balance while being very crucial to balance. It doesn’t take much, though. Even some games that let you begin with a random assortment of cards or resources might be enough to change some people’s decisions.
Solution 2: Personal Stakes
If your game is closer to the second example, where one player wants to make the same decision as another player but can’t, then maybe your game needs something personalized within the game. This can be more easily balanced than player powers, because they can be uniformly different. A classic one is just giving each player one space on the board, like one for each corner, that has some sort of role in the game. That way, players will be paying attention to different parts of the board. That might encourage them to focus on their corners of the board and not be as disrupted in their planning by other players.
Solution 3: Randomization
This is the scariest to some based on the game their making, but most games dodge this problem by having some form of randomization in the game. The market seen in most drafting games is perhaps the most common one: cards come out and are refreshed once bought so that there’s always something new. This beats the first scenario, because it’s impossible to get something already bought (though this is less because of randomization and more because of limited supply, which is also an option). It’s tougher for the second scenario, since the next player probably wanted the thing that last player took, but they are also getting shown a new card, which means that they aren’t going to be doing quite the same arithmetic. It also gives them an internal out to the thinking: if they think the next card showing up may matter, then they can just decide to not do the thinking until it does. This can sometimes have its own issues but it works for the problem of doing the same calculations multiple times.
Solution 4: Direct
This one is the obvious one, but I still thought I could bring it up. You could just be direct about it. Perhaps just disallow a player from purchasing the same thing as the last player, or make them pay extra. This is potentially pretty dangerous, though, because it gives the first player an advantage on top of their advantage.
Conclusion
And there you have it. Don’t give a player an excuse to do the same thing as another player, but also don’t give them a need to do the same mental work as another player. Let them act and think their own way so that they can provide the sort of variety necessary for a fun game.