1.  Download newest version of FETtec Configurator: https://github.com/FETtec/ESC-Configurator/releases
  2. ESC and FC have to be connected to each other. If your build is already complete, remove props!!!
  3. Connect ESC with Voltage 
  4. Connect FC to USB
  5. Choose your FC passthrough (KISS or Betaflight) in the FETtec Configurator and the COM port, then click "Connect"
  6. Download the newest Firmware version https://github.com/FETtec/ESC-Firmware/releases
  7. Click on "Local Firmware" and choose the downloaded file of the firmware
  8. (All ESCs are chosen automatically) click "Flash selected ESC´s"
  9. If its ready, all ESC beep and you can disconnect the ESC from USB and voltage
  10. ESC is ready to fly