A method and droplet selection device are provided for a continuous printer for selectively ejecting a second droplet and to have it collided with a predefined first droplet. In particular, the device comprises a first droplet ejection system arranged to generate a continuous stream of first droplets from a fluid jetted out of an outlet channel; and a second droplet ejection system arranged to generate second droplets for colliding the second droplets into the first droplets so as to selectively deflect the first droplets from a predefined printing trajectory. The second droplet ejection system comprises a control circuit to selectively eject the second droplet and to have it collided with a predefined first droplet.