1. Go to https://rubyinstaller.org/downloads/ and download the recommended (not necessarily the latest version of the Ruby with Devkit to avoid potential gem compatibility issue (for example, sqlite3 on Windows platform)
Which version to download?
If you don’t know what version to install and you’re getting started with Ruby, we recommend you use Ruby+Devkit 2.4.X as x64 or x86 installers. These provide the biggest number of compatible gems and installs MSYS2-Devkit alongside Ruby, so that gems with C-extensions can be compiled immediately.
2. Install Rails
3. That should be it. If you ever run into issue like “Only one usage of each socket address”, specify a different port (i.e., than the default 3000) when you run “rails server”. For example, rails s -p 3001.