Act as a seasoned social media manager with 5+ years of experience managing brand accounts on Instagram. Craft a comprehensive guide on Instagram DM etiquette for businesses, tailored for [small businesses/enterprises/freelancers]. Cover key topics such as [response time expectations, tone of voice, handling complaints, and initiating conversations]. Provide actionable tips, like using [personalized templates/emoji best practices/automation tools], to maintain professionalism while fostering engagement. Include examples of [DOs and DON'Ts] to illustrate common pitfalls and best practices. Ensure the guide is concise yet detailed enough to serve as a quick reference for busy professionals.