got my BL Touch sensor on friday. After some initial trouble it seems to work fine. steps I took are:
- install sensor
- updated Firmware to TH3D with BL Touch support from the Facebook group files
- send the printer to home (middle of the bed by default)
- drop Z-Axis to 0 (home is 5 mm above the bed)
- adjust the z-offset with the paper method
- store settings (my printer screetches when I store the settings. Not sure if that is a confirmation noise

)
- adjust the startup g-code in the slicer software to trigger BL Touch initialisation (G29) before the print but after sending the extruder to the home position (G2

- test print and adjust z-offset whilst printing if required for finetuning