Your orchids depend on a number of variables. Light, temperature, humidity, air movement, potting medium and size of the pot. The best way to decide whether your orchid needs watering is by sticking your finger into the medium. If it is moist delay watering. Always use room temperature water.

Feed with half-strength fertilizer at every watering; any balanced fertilizer will suffice. Water more often when the temperatures are high and the humidity is low especially in the summer. In winter reduce watering and feed.

I have received a lot of emails asking me what to do when my plant has stopped flowering. Should I cut off my spike etc?

My recommendations are:-
Cut it below the first flower if the plant is healthy. A side shoot will appear and will produce more flowers.
If the plant does not look healthy (signs to look for are yellow and limp leaves) cut the spike off completely.
Do not put the plant in direct sunlight. The best place is to place the plant in a bright window sill where there is no direct sunlight if you are growing indoors. If plants have insects on the underside of the leaf and leaf axils, use only a recommended orchid insecticide and make sure the plant is dry by evening.