Clone the folder or repository of the plugin you want to install to your ~/.config/astroid/plugins/ directory.

• Use one of the examples as your template.
• Update the plugin_name.plugin and plugin_name.py file
• Create a README.md file describing what the plugin does, preferably showing a screenshot and linking to installation instructions.
• Put this in a repository and publish it.
• Clone this repository and add the plugin-repository as a submodule.
• Submit a pull-request to this repository (or just an issue with a request to add the plugin-repository).

Some official plugins will be included directly in this repository.