Update local development instructions in README (#118)

* Comment explains AUTHOR bit better

* Separates installing prerequisites from running

* Tidies up Linux instructions (without attempting to correct them as I don't have Linux)

* Includes Windows instructions

README.md

@@ -8,6 +8,7 @@ Instead, please see our [company extranet][confluence-getting-started]
 for instructions on how to create a new page and view it before publication on the blog.
 
 ## Technical Stack
+
 The blog is a static website, designed to be hosted on [GitHub pages][github-pages].
 
 The underlying content is generated through a series of Ruby gems and libraries, starting with a dedicated github-pages [gem][ruby-github-pages].
@@ -31,7 +32,8 @@ If you wish to develop changes to the blog locally, you may find that there's a
 git clone --depth 1 --filter=blob:none --no-checkout [email protected]:ScottLogic/blog.git
 cd blog
 git sparse-checkout init --cone
-# modify this variable with the author name you wish to write posts under (typically derived from your SL email address)
+# if you want to write blog posts, modify this variable with the author name you
+# wish to write posts under (typically derived from your SL email address)
 AUTHOR='abirch'
 git sparse-checkout set _includes _layouts _data category scripts scss assets "$AUTHOR"
 git checkout gh-pages
@@ -45,7 +47,7 @@ __NOTE__: Instructions are work in progress.
 
 If you plan to use Docker, then you can [skip ahead][install-docker] now!
 
-The blog consists of static HTML pages with content generated using: 
+The blog consists of static HTML pages with content generated using:
 - [github-pages][ruby-github-pages] for deployment hooks
 - [Jekyll][jekyll-docs] for static site generation generator
 - [Kramdown][kramdown-syntax] for an extended markdown syntax
@@ -55,61 +57,97 @@ The blog consists of static HTML pages with content generated using:
 - [Bundler][ruby-bundler] to manage gems and dependencies
 - [Ruby][ruby-downloads].
 
-_In theory_, given that you've installed Ruby and Bundler, 
-and that the project contains a valid [Gemfile][project-gemfile],
-then using Bundler should bring in most of the dependencies automatically,
-however, due to Nokogiri's reliance on Native XML parsers you may require additional steps.
+_In theory_, once you've installed Ruby and Bundler,
+given that the project contains a valid [Gemfile][project-gemfile],
+then using Bundler should bring in most of the dependencies automatically.
+However, due to Nokogiri's reliance on Native XML parsers you may require additional steps.
+Thorough instructions for setting up your development environment are detailed below.
 
-### Docker:
+### Native environment
 
-Use a bash-compatible shell.
+#### Prerequisites
 
-**Install gem dependencies**
+First, install Ruby and (if on Linux) a few build dependencies for Nokogiri.
 
-First, output gem dependencies to a directory `container_gem_cache` on our host machine:
+On Linux:
 
 ```bash
-./shell/docker-gem-install.sh
+sudo apt-get install ruby2.3 ruby2.3-dev build-essential dh-autoreconf libxslt-dev libxml2-dev zlib1g-dev
 ```
 
-**Run dev watch**
+On Windows, if you use Chocolatey, simply run `choco install ruby` in a PowerShell instance
+with elevated priveleges. If you don't use Chocolatey, you can use [RubyInstaller][rubyinstaller]
+or see the Ruby website for [alternative ways to install Ruby][ruby-installation-instructions].
+You don't need to install any other dependencies on Windows at this stage.
 
-Now we can serve the blog:
+Secondly, update Gem and install the Jekyll, Bundler and Nokogiri gems.
+
+On Linux:
 
 ```bash
-BLOG_USERNAME=abirch ./shell/docker-dev-watch.sh
+sudo gem update
+sudo gem install jekyll bundler nokogiri
 ```
 
-Visit the blog at:  
-http://localhost:4000
+On Windows, in a PowerShell instance with elevated priveleges:
 
-### Linux:
+```bash
+gem update
+gem install jekyll bundler nokogiri
+```
 
-1. sudo apt-get install ruby2.3 ruby2.3-dev build-essential dh-autoreconf
-2. sudo gem update
-3. sudo gem install jekyll bundler
-4. Run 'jekyll -v' to check whether Jekyll is working
-5. bundle config path vendor/bundle
-6. gem install bundler
-7. sudo apt-get install libxslt-dev libxml2-dev zlib1g-dev
-8. sudo gem install nokogiri
-9. bundle install
-10. bundle exec jekyll serve
-11. Uncomment the lines in \_config.yml
-12. Access on http://localhost:4000
+Thirdly, configure Bundler to store project dependencies in `vendor/bundle`, and,
+when in the root directory of your clone of the blog, install the project dependencies.
 
-## Additional Tasks:
+```bash
+bundle config path vendor/bundle
+cd PATH/TO/BLOG
+bundle install
+```
+
+Finally, run `jekyll -v` to check whether Jekyll is working. If so, you're good to run the blog!
+
+#### Running in the native environment
+
+Once you've got all the prerequisites for your operating system, you can run the blog.
+Navigate to the root directory of your clone of the blog and execute Jekyll using Bundler.
 
-To minify JS, run:
+```bash
+bundle exec jekyll serve
 ```
+
+The blog will then be available on [localhost][localhost].
+
+If you need to re-compile the scripts or SCSS, you can use the NPM scripts.
+
+```bash
+npm install
 npm run scripts
+npm run style
 ```
 
-To minify SCSS, run:
+### Docker
+
+Use a bash-compatible shell.
+
+**Install gem dependencies**
+
+First, output gem dependencies to a directory `container_gem_cache` on our host machine:
+
+```bash
+./shell/docker-gem-install.sh
 ```
-npm run style
+
+**Run dev watch**
+
+Now we can serve the blog:
+
+```bash
+BLOG_USERNAME=abirch ./shell/docker-dev-watch.sh
 ```
 
+Visit the blog on [localhost][localhost].
+
 [confluence-getting-started]: https://scottlogic.atlassian.net/wiki/spaces/INT/pages/3577479175/Getting+started+with+the+Scott+Logic+blog
 [sparse-checkout-guide]: https://github.blog/2020-01-17-bring-your-monorepo-down-to-size-with-sparse-checkout/#sparse-checkout-and-partial-clones
 [github-ssh]: https://docs.github.com/en/authentication/connecting-to-github-with-ssh
@@ -119,10 +157,14 @@ npm run style
 [github-pages-docs]: https://docs.github.com/en/pages
 [jekyll-docs]: https://jekyllrb.com/docs/
 [kramdown-syntax]: https://kramdown.gettalong.org/syntax.html
+[localhost]: http://localhost:4000
 [ruby-github-pages]: https://rubygems.org/gems/github-pages
 [ruby-bundler]: https://bundler.io/
+[rubyinstaller]: https://rubyinstaller.org/
+[ruby-installation-instructions]: https://www.ruby-lang.org/en/documentation/installation
 [ruby-nokogiri]: https://nokogiri.org/
 [ruby-liquid]: https://shopify.github.io/liquid/
 [ruby-downloads]: https://www.ruby-lang.org/en/downloads/
 [project-gemfile]: Gemfile
-[install-docker]: #docker
+[install-docker]: #docker
+