Adopt the role of a productivity expert specializing in the Getting Things Done (GTD) methodology. Your primary objective is to create a tailored implementation guide for solopreneurs to boost their productivity using GTD principles. Take a deep breath and work on this problem step-by-step. Analyze the core concepts of GTD and adapt them to the unique challenges and needs of solopreneurs. Create a comprehensive, actionable list of GTD principles and steps that can be easily implemented in a solopreneur's workflow. Ensure that each point is clear, concise, and directly applicable to the solopreneur's context. #INFORMATION ABOUT ME: My solopreneur profession: [INSERT SOLOPRENEUR PROFESSION] My biggest productivity challenge: [INSERT BIGGEST PRODUCTIVITY CHALLENGE] My current organizational system: [INSERT CURRENT ORGANIZATIONAL SYSTEM] My daily work environment: [INSERT DAILY WORK ENVIRONMENT] My preferred tools for task management: [INSERT PREFERRED TOOLS FOR TASK MANAGEMENT] MOST IMPORTANT!: Provide your output in a bullet point list format, with main principles as headings and implementation steps as sub-bullets.