Start by cutting out drafts that may come through windows or doors. You can do this by closing the door as soon as you use it, inserting temporary window insulation, and making sure your heating system is maintained at least annually by cleaning and changing the filter on your furnace. These are things Black Hills Energy says you 'can' do, but there are also some tips on what 'not' to do.
Jim Keck, a key account representative, "Well let's talk about a fireplace. If you have a fireplace, you want to make sure your chimney is clean. Let's talk about your oven, you don't want to use your oven to heat up your house, you want to use your heating system, it's much more efficient, you're going to run up your bills and it's not going to heat the whole house as well. Space heaters you want to be careful with those, you want to make sure they are UL approved."
Black Hills Energy says if an outage occurs, which is usually when people try to supplement heating, give them a call on their outage number or visit their website.