Style guides can serve all kinds of purposes. For UI designers they are a library of design components. For writers, style guides are a reference for words and usage guidelines. Style guides are an excellent tool for teams to collaborate, especially as companies scale (it's very different working on a team of two vs. a team of two hundred). They ensure a level of consistency across all work, a unified look, feel, or voice, and save time by not having to start from zero each time you work on a project. Style guides can easily be updated as things change, need updating, or you encounter new challenges that need to be addressed.
Use a reference guide
When developing a style guide it's useful to start with an existing one to serve as a point of reference to build around and adapt. More traditional style guides include The Elements of Style, The Economist's Style Guide, and the Chicago Manual of Style (available online). You want to make sure you select a base reference that is relevant to the kind of work you are doing, and not one that is aimed at academic writing.
MailChimp's Content Style Guide breaks down content by different situations you may be writing for. The guide is written for MailChimp employees, but also acknowledges that it may be useful for others.
There are numerous online content style guides you can also refer to while developing a style guide of your own. As you review the guides take note of how they handle content, how long it is, and how examples are integrated.
Show, don't tell
One of the most effective ways to communicate in a style guide is to include examples. When you put an example of good and bad text next to each other, it's a memorable way to point out the value of strong content and the difference a few words can make. These examples are also helpful when you share the style guide with new team members, or someone from another department, such as marketing.
When you see an example of active vs. passive voice, it is much easier to understand it in context beyond just the definition of the terminology. It's also useful to integrate exceptions to any rules.
Active voice presented in the MailChimp Content Style Guide.
Consider voice and tone
Every brand has it's own voice, just as every individual has their own personality. What the brand says, and sounds like is what makes the brand what it is. The voice should be consistent, but the tone is how it adapts for different situations. For instance, if a customer is frustrated by an experience and is looking for the contact information of the company so they can complain it's probably not the best time to integrate humor into the tone of the response.
The text on the homepage of MailChimp's Voice & Tone guide reads, "Before you write for MailChimp, it’s important to think about our readers. Though our voice doesn’t change much, our tone adapts to our users’ feelings. This guide will show you how that works."
While MailChimp has a more playful voice, 18F the US Digital technology service is more serious, but still friendly and conversational. Here's how they describe their voice:
It's essential to think about how the user or customer is feeling at various stages of the journey. Consider what tone is appropriate for each circumstance. Remember to think about situations that are going well for the user, as well as when they may be stuck or encounter an error.
Be comfortable (and consistent) breaking the rules
What's important to keep in mind with your product content is that you want it to sound human and accessible. Sometimes this may mean breaking grammar rules. If the content team decides to break a certain rule, it's something that should be addressed in the style guide.
Digital tools for writing
As you're defining grammar usage for your style guide, one resource you may want to check out is Grammarly. It's an online plugin that checks spelling and grammar as you type. (It also sends you recaps for the number of words written, or mistakes caught each week.). The Grammarly blog also showcases grammar tips to help address grammar related issues you may encounter.
Hemingway Editor app is a digital tool that is popular with content strategists. It highlights text in different colors to point out problematic sentences or phrases that are awkwardly long. It can be a great way to help you write in a more clear and concise manner.
Both of these tools may be useful as you think about how you want to approach your style guide, language, and word choice.
Refer to existing style guides as you develop your own.
Use examples in your style guide to display each concept or rule.
Consider tone and voice.
Use language and grammar that is relevant to your brand or product voice.