To care for a Euphorbia 'Trigona' African Milk Tree, provide it with 6-8 hours of direct, bright sunlight daily, use well-draining soil and a terracotta pot, and water sparingly only when the soil is completely dry to prevent root rot. Fertilize lightly during its growing season in spring and summer, but not in fall or winter. Protect it from freezing temperatures and be cautious when pruning, as the white sap it produces is poisonous and can irritate skin.