Mrs. Green-thumb Reporting...
Watering: Make sure you have good drainage around the roots to prevent rotting; or better yet, leave a watered plant in your sink or tub to drain.
When should I water the plants? The easiest way to tell if your earth sister (lol) is thirsty, pick her up. If she's heavy, you watered her recently; if she's light as a feather, give her a drink! Generally speaking, water once a week for green plants, and every 3-5 days for blooming plants depending on sunlight (food production).