The two strands of wire together need to pass through the center of the toroid 18 times, for the pair. In your photograph, you have 4 turns on the toroid for the pair.
If you have two strands of wire that were originally about 3 feet long, wind them on until you have either completed 18 turns, the toroid is too full to wind any more, or the wire gets too short to wrap any more turns on.
Try to keep track of how many turns that you have wound on.
If you have two strands of wire that were originally about 3 feet long, wind them on until you have either completed 18 turns, the toroid is too full to wind any more, or the wire gets too short to wrap any more turns on.
Try to keep track of how many turns that you have wound on.