Finalization of the circuit of a household fan with a humidity sensor

Hello! I bought a fan with a humidity sensor model: ERA 5S HT. But it works only from a humidity sensor, that is, it turns on and off at his command. In addition to this, I also need to turn it on from the switch. Can you help? How to connect a switch to the circuit of this device? Maybe directly to the motor bypassing the board? But in this case, I will not give power to the board on the other hand? Or it can put 2 diodes there to prevent this.
The board is equipped with a third contact that is not soldered, I found a similar model where the switch is soldered to this contact. (https://www.youtube.com/watch?v=9TtfMAmKXJo).