How to Safely Install Nulls Brawl APK on Android

I've heard a lot about Nulls Brawl APK and I'd like to try it out on my Android device. However, I'm concerned about the safety of downloading and installing APK files.

Can anyone provide a step-by-step guide on how to safely install Nulls Brawl APK? Are there any trusted sources and precautions I should take to avoid malware or other issues?