Gabriela Castillo outlines an effective communication process to ensure that instructions from an important meeting with superiors are properly communicated to all relevant parties. Key steps include: 1) Taking thorough notes during the meeting to capture all instructions. 2) Sending the instructions to subordinates, suppliers, and clients organized by region and area of responsibility. Instructions should be tailored to each target audience. 3) Following up on the instructions by maintaining ongoing communication, such as via email and phone calls, to ensure proper implementation and provide feedback to superiors.