Formatting: headings, images, buttons

You write your email as readable text; formatting is a light layer on top. The toolbar inserts the syntax for you, and the live preview shows exactly how it renders—but it helps to know what the marks mean:

• ## Section heading—a section heading with an underline rule (use # for one big top heading)
• **bold** and *italic*
• [label](https://link)—a labeled link
• ![caption](image-url)—an image, centered, with the caption underneath
• [button: Get the book](https://link)—a real button, in your brand colors
• - item at the start of a line—a bulleted list (1. item numbers it instead); the toolbar's Bullets and Numbers buttons do this for you
• --- on its own line—a divider rule
• A blank line starts a new paragraph

Images

Use the toolbar's image button to upload straight from your computer—images are resized and compressed automatically. Click an image to pick its size—quarter, third, half, three-quarter, or full width (in the raw text, extra ! marks and a digit spell the same thing: !4 quarter, !3 third, ! half, !! three-quarter, !!! full)—and selecting an image then clicking Link makes it clickable—handy for book covers.

Why it works this way

Every email is sent in two forms: the formatted version, and a plain-text version derived from the same source (links become "label (url)", buttons become "Label: url"). Spam filters like emails that carry a good plain-text part, and some readers prefer it—you get both for free by writing this way.