Thanks for considering working on MUTGOS! I hope you decide to join us!
First off, please abide by the Code Of Conduct. With that said... anyone is welcome to contribute! We welcome C++ coders, AngelScript coders, web developers, documentation people, UI/UX people, architecture/system designers, testers, end users, bug reporters, and more! If you want to help but aren't sure what you can do, contact the project lead(s) and we can help you out.
Other than following the other guidelines (style guide, etc), please talk to a project lead before starting work on a task. This can be done by writing a new issue, responding to an issue, email, etc. The discussion should entail, at a high level (and can be brief), how you intend to fix or add new functionality (or documentation, tests, etc), questions you may have, and concerns.
If the lead(s) has no concerns with your approach, feel free to start working on your contribution when you have time! The goal of asking up front is to make sure you're not doing duplicate work, or work contrary to the development of the software. Basically, it's to avoid wasting your valuable time.
Before making a pull request for any generated artifact, please make sure you've tested and re-reviewed your own code thoroughly. If this is a non-code artifact, please do spell checks, etc.