Final answer:
To plant an avocado seed, suspend it in water using toothpicks until it sprouts roots. Then, transplant the seedling into a pot with soil.
Step-by-step explanation:
To plant an avocado seed, first remove the seed from the fruit and rinse off any excess flesh. Use toothpicks to suspend the seed over a glass or jar filled with water. The toothpicks should be inserted into the seed at a slight angle, allowing the bottom half of the seed to be submerged in the water. Place the glass or jar in a warm and sunny location, and ensure that the water level is maintained. Eventually, the seed will sprout, and roots will start to grow. Once the roots are well established, you can transplant the seedling into a pot with soil, taking care to keep the root intact. With proper care, the seedling will continue to grow into an avocado plant.