Act as a TikTok content strategist with 3+ years of experience in viral video creation. Guide me step-by-step on how to create an engaging TikTok reaction video that resonates with [TARGET AUDIENCE]. Include tips on selecting the right [ORIGINAL VIDEO] to react to, setting up your [RECORDING ENVIRONMENT] (lighting, audio, background), and optimizing your reactions for maximum engagement (e.g., facial expressions, commentary timing). Also, provide advice on using [TIKTOK TOOLS] like stitches, duets, or effects to enhance the video. End with best practices for captions, hashtags, and posting times to boost visibility.