Bring in that sun!
Taking advantage of the sun is key to keeping warm while you wait for your heating system to be repaired. During daylight hours, let as much sunlight into your home as possible. That means opening up your blinds and/or curtains!
Keep the heat in.
Winter nights can be the most unforgiving, especially here in Vegas. So, try to keep as much of the heat which was gathered during daylight hours in. You can do this by closing your curtains and blinds as the sun sets. Insulating your home will also help keep that heat in.
Have ceiling fans? Activate "Winter Mode".
That's right! Most ceiling fans have a setting designed for the winter months. What this does is reverse the direction the fan blades move, bringing all the warm air that is rising upward to your roof back down into your rooms and circulating through out your home.
Combat the Stack Effect.
What is the "Stack Effect"? The Stack Effect is when warm air rises and ultimately escapes, cold air comes rushing in to replace the warm air, kinda like a vacuum. Many homes (especially tall or multi-story homes) suffer this effect. To combat this, seal up any gap that may pull in cold air such as the gaps under your doors or your windows. The goal is to create somewhat of a house bubble, trapping the warm air in while blocking the cold air out.
Purchase a space heater.
Space heaters or portable heaters are fairly inexpensive and could heat up a decent sized room depending on the heater. BEWARE: these heaters have been known to burn down homes and cause serious injury and death. Always keep the heaters away from flammable material and constantly monitor them. When using, be sure to close the door to the room it's warming as they are not meant to heat more than a single room. Turn it off once you leave the room, keeping the door closed as to not let the heat escape.