What essential tools help beginners mod safely and troubleshoot conflicts?

[Scarlett61]

I've been playing a lot of a certain open-world RPG and want to start experimenting with mods to improve visuals and add some quality-of-life features, but I'm completely new to modding and worried about breaking my save file or causing instability. The modding community for this game is huge but a bit overwhelming. For experienced mod users, what are the essential tools and practices for a beginner to safely install and manage mods, and how do you troubleshoot conflicts when something inevitably goes wrong?