Volunteer moderators actively engage in online content management, such as removing toxic content and sanctioning anti-normative behaviors in user-governed communities. The synchronicity and ephemerality of live-streaming communities pose unique moderation challenges. Based on interviews with 21 volunteer moderators on Twitch, we mapped out 13 moderation strategies and presented them in relation to the bad act, enabling us to categorize from proactive and reactive perspectives and identify communicative and technical interventions. We found that the act of moderation involves highly visible and performative activities in the chat and invisible activities involving coordination and sanction. The juxtaposition of real-time individual decision-making with collaborative discussions and the dual nature of visible and invisible activities of moderators provide a unique lens into a role that relies heavily on both the social and technical. We also discuss how the affordances of live-streaming contribute to these unique activities.