John Saito, on Medium, has 7 tips for designing words. The best is the final one:
7. Write in mocks, not docs
Have you ever written something that looked good on paper, but ended up looking too long when it went live? That’s what happens when you do your writing in Google Docs, Dropbox Paper, or any other writing app.
When you write words for an interface, seeing the full context is so crucial. You need to know how your words are going to look next to everything else around it.
That’s why I prefer to write in Sketch mocks, not in docs. I find that writing in mocks helps inform my writing decisions, because I can see how my words will look in context.