Download and unzip it, then move its contents (a folder called LIBFREDO6_Dir_xx and a file called LibFredo6.rb) into your Plugins folder. I highly encourage you to support his efforts.
Fredo6 makes his plug-ins available as donationware, meaning that they're free to download and use, but that payment is always gladly accepted.
There are plenty of settings in the toolbar that appears in your modeling window when you activate one of the tools take a look at the plugin’s handy documentation to see what everything does ( Tools > Fredo6 Collection > RoundCorner > Documentation.) When you're ready, click somewhere in empty space to run the script. Increasing the number of sides on your rounded corners increases your face count exponentially.
