The best thing I've even seen in this space is the Brand Strategy Canvas. It's like the Lean Canvas or Business Model Canvas but walks you through the positioning and messaging for a startup.

At my last company, we didn't use it and had pieces of a strategy, message, and an awful name. Then we sat down and spent ~2 hours and worked through it block by block. It was painful but on the other side, we had a better name, a clearer Vision, a simple way to describe that Vision, and lots of sound bites to use in conversations, blog posts, etc.

My only complaint is that we didn't do it a few months earlier.

Here's a video of the creators walking through it: https://vimeo.com/112098978