If the template you're contrbuting to is in https://www.github.com/github/gitignore, add your changes to a <template-name>.patch file otherwise add a new <template-name>.gitignore file.
If the template you're contrbuting to is in https://www.github.com/github/gitignore, add your changes to a <template-name>.patch file otherwise add a new <template-name>.gitignore file.