What are the best strategies for building a competitive green-white-black Commander deck?

To build a competitive green-white-black Commander deck, focus on a strong mana base with ramp cards, include versatile removal spells, and prioritize powerful creatures and synergistic combos. Additionally, consider including cards that provide card advantage and ways to protect your key pieces. Lastly, fine-tune your deck through playtesting and adjusting based on your local meta.