First, according to the planting requirements of bonsai pots in the future, trim and saw off the stumps, and then find a large flowerpot. First cover the stump with soil, then plant it in sandy loam, and slowly fill it with soil to fix it. It's late autumn, so we should put it in a place sheltered from the wind and sunny, and water our feet. Then continue to pile up and cover the stump with pure sand, leaving only some branches and leaves in the open air. Be sure to keep the sand moist in the future, and continue to raise piles for 1-2 years next year, then you're done.