Based on the insights provided by executive coach Ed Batista, there isn't a specific amount of practice required before starting as a coach that is universally applicable. However, Batista emphasizes the importance of continuous improvement and development of coaching skills through various exercises and reflection.

From the excerpt "Fishbowl Coaching (A Group Exercise)," Batista outlines a group exercise that can help aspiring coaches develop their skills within a small group setting in under an hour. This exercise involves multiple rounds where participants take turns acting as coach, coachee, and observer. It is designed to provide practice in coaching and receiving feedback on the coaching process.

In "Connect, Reflect, Direct...Then Ask (On Coaching)," Batista discusses the importance of connecting with the coachee, reflecting on their responses, directing their attention, and asking questions that build upon the conversation. This suggests that practice should involve honing these specific skills and being mindful of how to effectively engage in a coaching conversation.

Batista also touches upon the concept of "Conscious Competence in Practice," where he encourages identifying specific activities or disciplines within the coaching process and reflecting on one's current level of competence in each area. This implies that practice should be targeted towards areas where one needs feedback, guidance, practice, or a new challenge.

Lastly, in "Open Space, Deep Work, and Self-Care," the importance of self-care for coaches is highlighted, which includes mindfulness practices. Mindfulness can enhance a coach's ability to manage attention and remain calm under stress, which is beneficial in coaching interactions.

Overall, practice for an aspiring coach should include:

• Engaging in group exercises to practice coaching and receive feedback.
• Developing the ability to connect, reflect, direct, and ask questions in coaching conversations.
• Identifying areas of competence and incompetence and working on them.
• Incorporating self-care practices to support one's effectiveness as a coach.

There is no set amount of practice that guarantees readiness to start as a coach, but regular, reflective practice that focuses on developing specific coaching skills and self-awareness will contribute to one's preparedness for the role.