[header] How to smoke in your house without people knowing [title] Open a window or fireplace duct. [step] Before you start smoking, it's very important you give the smoke an exit to escape. Without an open window or duct, the smoke will linger in the room and your health will be at risk. 
Depending on the room you're going to smoke in, there should almost always be some window to open. [substeps] A fireplace duct is an even better choice, as fireplaces are specifically designed to let smoke escape.