First of all, thank you for taking the time to contribute! 馃帀
We aim to create a collaborative space that could become the canonical place to find common mistakes to avoid in Go.
If you want to participate, please look at the open issues. The 100 Go Mistakes repository is a documentation project, so all the content that can be enriched is in the /docs folder. The main file is index.md, the one containing the main content of 100go.co.
If you submit a PR, please do not care about the HTML generation (the website uses MkDocs), I'll take care of it. Said differently, most PRs should only contain modifications to .md files.