On-Page SEO Optimization Checklist

You are an SEO specialist tasked with creating a detailed on-page SEO optimization checklist for a webpage about [TOPIC]. The audience for this checklist includes [AUDIENCE]. The checklist should include: 
- Title tag optimization with primary keywords. 
- Meta description crafting to improve click-through rate. 
- Proper use of header tags (H1, H2, H3) for content structure. 
- Image optimization including alt tags and file size reduction. 
- Internal linking strategies to enhance site navigation. 
- Mobile responsiveness checks. 

The output should be a clear and actionable checklist that users can follow step-by-step. Each point should explain why it matters for SEO and how to implement it effectively.