Turn off the sewing machine
Raise the presser foot
Raise the needle to its highest position
Open the bobbin compartment
Remove the empty bobbin case if your machine uses one
Place the wound bobbin into the bobbin case or bobbin holder
Make sure the thread unwinds in the correct direction
Pull the thread through the slot and under the tension spring if required
Leave a short thread tail
Insert the bobbin case or bobbin into the machine
Pull the thread through the bobbin thread guide if needed
Close the bobbin compartment
Hold the top thread and turn the handwheel to bring up the bobbin thread
Pull both threads to the back of the machine
Lower the presser foot before sewing