Best way to manage risk in sports betting

Trying to understand how people avoid losing everything when betting on sports. It feels like even when doing research, results can still go the wrong way. Sometimes a bet looks safe but ends up failing for unexpected reasons. Curious how experienced bettors handle risk and decide stake sizes. Is there a simple way to keep things under control without overthinking every single bet? Looking for practical advice that can be followed daily, not complicated systems or theories that are hard to apply.