There are different ways to install plug-ins. BioUno has some Jenkins plug-ins that have to be installed manually. You can find the complete documentation for installing plug-ins in the Plug-ins Wiki page from Jenkins project.
From the main screen, go to Manage Jenkins and in sequence to Manage Plugins.
There you should see a screen with four tabs. Looks for the Available tab. Clicking on it will bring the list of available plug-ins, organized by categories.
As we've talked about notifications prior, look for the email-ext plugin. This plug-ins adds more options for sending notifications from your builds.
In newer versions of Jenkins you can install some plug-ins without having to restart. All you have to do is just click on Install without restart.
Wait until the screen is refreshed and voilà, you have just installed your first plug-in.
In order to install BioUno Jenkins Plug-ins, you will have to add our update site.