Preparation materials and tools: baking soda, watches, toothbrushes, rags.
Step 1: First, pour out a proper amount of baking soda powder, as shown in the following figure:
Step 2: Dip baking soda into the toothbrush and start scrubbing the strap, as shown in the following figure:
Step 3: Rinse both sides of the strap with clean water after brushing, as shown in the following figure:
Step 4, then dry the water on the strap with a rag, as shown in the following figure:
Step 5: After the final cleaning, the yellow belt problem is solved, as shown below: