To prepare corn bait for carp fishing, the materials you need to prepare include: container, old corn, honey, monosodium glutamate, and koji wine.

1. First, put an appropriate amount of cooked old corn kernels into the container.

2. Then add an appropriate amount of MSG.

3. Add appropriate amount of honey.

4. Then add an appropriate amount of koji wine until the corn kernels are submerged.

5. In this way, the corn bait for fishing carp is ready.