Preheat the bed and nozzle to your usual printing temperatures
Home all axes
Disable stepper motors if needed to move the bed manually
Move the nozzle to each corner of the bed
Place a sheet of paper between the nozzle and bed
Adjust each bed leveling knob until the paper has slight resistance
Repeat the corner checks until all corners feel the same
Check the center of the bed and adjust if needed
Recheck all corners after the center
Set the Z offset if your printer firmware supports it
Print a first-layer test and fine-tune the knobs if necessary