This is a LaTeX document class for making a Master's thesis at the University of Helsinki. This template abides by the conventions followed over the years in physics and physics-related disciplines (astronomy, geophysics, meteorology), and has recently been updated to include some changes made to the thesis layout in the 2017 teaching reform (Big Wheel).
Keep the HYgradu.cls file and sinetti.pdf in your working directory when writing the .tex file.
Add HYgradu.cls and sinetti.pdf to your LaTeX distribution tree to use it from any directory. Of course, this is a package you only usually need once so it's not that important.
The simplest way is just to take the template provided with the class file and start editing that.
Please send any bug reports or suggestions to olli.wilkman@iki.fi. Contributions on GitHub are also welcome.