If a portable air conditioner is in a room with a window, assemble the window kit it came to vent the hot air outdoors. For rooms without windows, set up the unit to vent hot air out of the room through a sliding door, wall or drop ceiling.
To assemble a standard air conditioner window kit, place the unit within a few feet of a window, depending on the length of the supplied vent hose. Most vent hoses are about 4 to 5 feet in length. Attach the window bracket to the window, and trim it if necessary to achieve a snug fit. Then, attach one end of the vent hose to the air conditioner and the other end to the window bracket using the vent hose adapter. After shutting the window tightly, the air conditioner should be ready to vent hot air outside.
If a window is not available, an alternative is to attach the window bracket to a sliding door and use a material like plywood to seal the rest of the vertical opening. Another option is to cut an appropriately sized hole in the wall through which the unit can vent hot hair. A jigsaw is useful for cutting the hole, and silicone caulk works well for sealing the edges of the hole after venting the air conditioner. If none of these options are feasible, a final option is to purchase an air conditioner that comes with a built-in mounting system for attaching the unit to a ceiling panel.