There are many methods of releasing the queen.
We recommend sitting the queen cage, with the queen and escort bees still inside, in the queenless hive for 24 hours. This will get the colony used to the new queen’s pheromones and allow for a better acceptance. You can place the cage on top of or in between the frames, with enough space that the bees can feed the queen through the mesh. Generally, the queen is better accepted when there are no open brood cells within the hive. This is because the colony may try to produce their own queen from the open brood, and choose not to accept the introduced queen.
After 24 hours, the plastic gate on the queen cage should be cracked open. From there, the bees can eat through the candy, releasing the queen into her new hive.