Around the house
Prevent bursting pipes by keeping the house above 65 degrees and occasionally opening cabinet doors in the kitchen and bathrooms since the temperature inside the walls, where the pipes are located, is substantially colder. Keeping cabinet doors open allows the warm air to circulate around pipes, particularly in the kitchen and bathroom. Also, keep the water trickling, especially through outdoor pipes and faucets connected to pipes that run through an unheated or unprotected space.
Make sure your dishwasher, clothes washer and dryer are full before using them to prevent unnecessary water waste.
Filter your own water and fill up your own reusable bottles instead of buying bottled water. This is not only more environmentally friendly, but cheaper in the long run.
Save money on your electric bill by shutting down and/or unplugging idle electronic devices.
In the yard
Re-mulch your gardens to keep the ground frozen and shield it from the warmth of the sun. A steady temperature will keep your plants in dormancy and prevent it from triggering new growth during a brief warm spell. Tender, new growth too soon will just result in more winter die-back.
Check outdoor plants for animal damage and lingering pests and rodents. If there is damage, use plant protectant to ensure that your plants are untouched during the rest of the winter.