Right out of the box, Cura is pretty powerful. But, sometimes you still just need a little extra functionality. Fortunately, Cura makes this pretty easy to implement. Here is how I do it. Once I figure out which plugin I want to use, I add my login information into Cura. This synchronizes the software on my laptop to my account on the cloud. Then I go to the Ultimaker Marketplace on the web and find the plugin directory. You can add plugins from Cura itself, but I have found it to be very laggy and difficult to use so I just do it from the web. Pick the plugin(s) that you want and add them to your account. Restart Cura and it will ask you to synchronize your account.