Farhan's original code has some bugs and is incompatible with the latest version of the Si5351A library.
The current basic Raduino code no longer uses the SI5351 library at all. It is found here:
Click on the green "Clone or Download" box and select "Open in Desktop" or "Download ZIP"
The ZIP file contains the following files:
UnZIP these files to the directory of your choice where you keep your Arduino sketches.
README.md is a Markdown file which can be read with Wordpad.
Remember that the raduino.ino sketch must be in a folder named raduino.