Hia, feel free to make a fork and pull request. I'm actually just in the process of pushing new code that makes the page output more structured which should make templating much easier, along with a bunch of new sitewide settings.
How to install REforum on my website?
After that, connect to your site via FTP and upload all the reforum files onto the server in your destination of your choice.
What do I use to connect via FTP? FileZilla?