Feeding an Orchid Cactus correctly is really important. You can use a well balanced plant food once a month. During the winter the plant needs a 8-10 week rest. Water less and don’t feed the plant at all. In late fall (October to November), about a month before spring, give your Orchid Cactus some plant food low in nitrogen but high in potash. Nitrogen encourages green leaf growth and that’s not what you want to do now.

Other than that just basic care:

bright indirect lightVery few houseplants should be placed in direct sun. High light refers only to bright indirect light since direct sun often burns the leaves of indoor houseplants. An area that is too hot and dry encourages Spider Mites and causes blooms to quickly fade. A northern exposure really doesn't provide enough light for high light plants. These plants need to be placed directly in front of an east-facing window, within 1-3 feet of a west-facing window, and within 5 ft. of a south facing window. A high light area has over 300 ft. candles of light.

Moist soil spring through fall, less water in winter, but never let the soil totally dry out

Regular pruning to keep the plant full (use the cuttings to start a new plants)