There are several designs of self-watering containers that work fairly well. They have a water reserve at the bottom of the pot that can be accessed by the plant root or a wick as needed. A good self-watering container can provide water for several weeks at a time. Polymer crystals can be mixed into the soil. The crystals look like big rock salt when they are dry and swell to look almost like chunks of clear Jello when they are wet.
Excess water is absorbed when the plant is watered and slowly given off as the soil dries.
There are fancy wick systems and capillary mats available in specialty gardening catalogs. If you have several valuable plants, you may want to check into these systems. Providing Light You can increase the amount of natural light available to your plant by making sure the drapes are wide open and the plant is as close to the window as possible. Also, make sure one plant isn't being shaded by another. If you'd rather not leave your drapes open, you can use artificial lights.