The Mystery Knit Cable Scarf 2025 uses the 1/1/1 LC (Left cross) in clue #5. It is much faster to learn to work this cable stitch without a cable needle.
The 1/1/1 LC with a cable needle instructions are as follows: Slip next stitch to cable needle and place at front of work, slip next stitch to cable needle and place at back of work, k1, k1 from back cable needle, then k1 from front cable needle.
Using a cable needle for this cable, you will need to work with 2. It is much easier to work this cable without a cable needle.
I have created a video to help you to learn how to work this 1/1/1 RC without a cable needle.