For a structured, step-by-step process, the guide on Mejoress is excellent. It breaks down the DLC into easy steps, covering everything from the game's opening lines of dialogue to solving the complex vent puzzle.
Ensure the master bedroom or the study is empty. You may need to use the alcohol or trigger side quests for characters like Brittney or Patrick to move them away. house party liz katz guide link
Look closely at the external AC unit to spot a stuck inside. Click the knife to "Inspect" it. For a structured, step-by-step process, the guide on