Format Slack Messages

** Emphasis **
To emphasize words or phrases, surround your text with asterisks to create bold text, or underscores for italic text.

Strikethrough
Try using strikethrough to show corrections in your messages, or mark completed items on a to-do list. Surround your text with _tildes to strike out.

Lists
To create a list, use Shift + Enter to create new lines in your message, then add a number or a bullet (•) before each item.

Tip: To add a bullet point (•) from the comfort of your keyboard, try Option + 8 on a Mac

Blockquotes
Add angle brackets to the beginning of your message for an indent or blockquote:

to indent one paragraph

to indent multiple paragraphs

Code blocks
To display a portion of text as fixed-width code, surround your text with backticks:
single backticks display fixed-width text along with your other message text
triple backticks create a block of pre-formatted, fixed-width text

Reference from slack help