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.agents/skills/substack-expert/references/formatting-best-practices.md

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+# Substack Formatting Best Practices
+
+## Text Centering
+
+Substack's minimalist editor lacks a standard center-align button for regular body text. To center text: select it, click "Insert Quote", then choose "Pull Quote". This creates a visual break ideal for highlighting key phrases or statistics.
+
+## Content Hierarchy
+
+- Use **Heading 1** through **Heading 3** to create a clear, scannable structure.
+- Keep paragraphs short (3–5 sentences max) to maintain readability in both email and web views.
+- Use **Bold**, *Italics*, ~~Strikethrough~~, and hyperlinks to guide the reader's eye and improve scannability.
+- Use bullet points, numbered lists, and dividers to break up long sections.
+
+## Quotes
+
+- **Block Quote**: For clearly attributing long excerpts from external sources.
+- **Pull Quote**: For emphasis on a key phrase or statistic; renders centered and visually distinct.
+
+## Visuals and Media
+
+- Insert images, GIFs, or charts to break up heavy text.
+- Image width options: **standard**, **wide**, or **full** — choose based on the visual weight needed.
+- Always add a **caption** and **alt text** to every image. Alt text serves accessibility and organic SEO simultaneously.
+
+## Interactive Engagement Tools
+
+- **Native buttons**: "Subscribe", "Share your post", "Leave a comment".
+- **Custom buttons**: Insert any URL to drive a specific reader action (e.g., download, survey, external link).
+- **Polls**: Exclusive to paying subscribers; functions as a passive engagement and retention mechanism.
+
+## Email Subject Line Rules
+
+- Keep subject lines under 50 characters to prevent truncation on mobile.
+- Avoid ALL CAPS, excessive exclamation marks, and spam-trigger phrases like "Buy Now" or "Act Now".
+- Test deliverability by checking spam scores before sending to the full list.