Glad to hear that you want to contribute! You can have a look at our validation documentation page as mentioned by @AnnaFless. Follow the exact pattern of the validation and try to give all appropriate information most importantly:
- dimension, boundary conditions, formulas, results (graphical or tabular), references.
Once you are finished, just put all of this information in your comment field under your project. We will then make a documentation page of it and link it to your project.
If you have any question/s, feel free to ask.