If you're going to be away from your plants for a long weekend:
If you can't find a dependable plant sitter, cover each plant or small group of plants with plastic. Use bamboo stakes or metal hangers to keep the plastic above the leaves. Place plants out of direct light. Turn thermostat down. Such flimsy terrariums will keep plants alive up to 3 weeks.
Another Idea: Lay plastic in your bathtub. Cover the plastic with newspaper, then wet the papers. Thoroughly water your plants, then set them in the tub. Cover with plastic to keep humidity high. Moving? Click here to learn how to safely transport your houseplants.