Make groups of as equal numbers as possible and divide them over baskets with some space between them.
Let the next player in line take a penalty throw.
Let them all take the penalty throw at the same time at your indication (with or without whistle), this simulates the pressure that is present in a competition environment.
The group that scores 5 penalty throws first gets a bonus life (see variant B).
You can repeat this variant a few times (depending on the size of the group).
Variant B.
You now move on to shooting; the pressure to score a penalty throw increases.
Starting position is the same as variant A, however, the player who misses the penalty throw is now out.
Unless a bonus life previously earned by the group is used.
That means the group shrinks.
The last two groups with 1 person left, will compete against each other on 1 central basket.
The players who were shot earlier form a (large) circle around the scene.
The remaining players take turns to score a penalty throw; the one who manages to score two penalty throws before his opponent manages to score at all, gets the honorary title of king (or queen ) of the week.
At x-moment you can deliberately introduce some disturbing elements, such as loud music, or an extra ball in the field to get the players out of their concentration. Explain clearly what the purpose of this is.