At Clarity Conference in San Francisco, Anna Pickard discussed everything that goes into creating a cohesive voice and tone at Slack. Here are my notes:

• Anna works at Slack, and is tasked with making a style guide to deal with the company's fast growth. The goal is to maintain a consistent tone of voice, as they want Slack to feel like another member of your team. How do you scale that?
• Rules: glossary and grammar, oxford comma, emdash, etc.
• They created a Gloss Bot, which is a Slack bot that pulls up definitions and rules around grammar
• Voice and tone: Asking people to be like you ends up with them doing a bad impression of you. How do you sound human and strike the write tone?
• Slack looks for opportunities to communicate in a human way with their users. Loading messages contain human language, and their release notes are famously long. They get people excited about using the application and serve as a learning opportunity. Tweets are general and positive. Error messages contain empathy for the user.
• Style rules: important to define what you don't sound like and what you don't do.
• Looked at MailChimp's Voice and Tone as a starting point. This but not that is a good place to start.
• Break down the voice into shared characteristics of the brand.
• Empathy: Who am I talking to? What emotional state are they in? What is the context? What do I want them to take away from this?
• Courtesy: getting out of people's way and letting them get out of the way. Am I providing the information people need? What can I do to simplify this message? How does this help the user? Is this actually intuitive? Do I need speak at all? Take the time to write concise stuff.
• Craftsmanship: let people know how and why you're making the decisions you're making. Work as transparently as possible. Is this as good as I can make it? Could someone else make it better? What are the options?
• Playfulness: have an open mind. What do error messages (amongst other things) usually sound like? How can I do this differently? Put a different spin on it.
• Honesty: be open and honest and fair to your users. Is this really what I want to say? Is this really the way I would say it? How human does it sound if I read it out load?
• Creating a style guide is about finding a "unity of intention."