What are the important considerations in caring for orchids?

As they said every type has a specific requirement in terms of amount of sunlight, water, humidity and all that stuff. But, there is a general rule to it that you can apply. In watering orchids they don't like too much water, general rule is water them once every week or when the medium is completely dry. For sunlight requirements, most orchids come from the tropics so they need a good deal of diffused light. They need twelve hours of sunlight (at most) each day, but avoid the afternoon sun as they too strong and can burn the leaves. Orchids that thrive in low light conditions like Phalaenopsis can be placed indoor, but still they need light so place them near a window early in the morning or evening, again avoiding the afternoon sun.