Act as a seasoned digital marketing strategist with 10+ years of experience in startup growth. Provide a detailed guide on the best ways to use SMS marketing for [BUSINESS TYPE], focusing on [TARGET AUDIENCE] and [KEY OBJECTIVES]. Include actionable tips on crafting compelling messages, timing strategies, and compliance with regulations like GDPR or TCPA. Highlight how SMS can complement [OTHER MARKETING CHANNELS] and share real-world examples of successful campaigns. Keep the tone professional yet engaging, and ensure the advice is scalable for startups with [BUDGET CONSTRAINTS].