Once you have tested your new plugin, using the runtime workbench, it is time to deploy your Node as a plugin. This is done by using the "Export deployable plug-ins and fragments" wizard. Just right-click your plugin and choose "Export...". In the window that appears select the "Plug-in Development" folder and within this, the "Deployable plug-ins and fragments" wizard. After pressing the "Next" button the wizard displays a list with all available plugins in your workspace and the one you right-clicked is selected. Thus, you just have to select a directory to deploy your plugin to or an archive file. In case you select a directory the plugin is exported to this destination within a directory called "plugin". This directory then contains the plugin as a .jar file. In case you select an archive file, the "plugin" folder containing the .jar file is zipped to the specified archive.
Once, the plugin is exported it can be installed in any KNIME installation or any Eclipse installation that contains the basic KNIME plugins by copying the content of the "plugin" folder to the "dropins" folder of the KNIME / Eclipse installation. Note that you have to restart your installation in case it is currently running.