All Oncidiums prefers lots of light in order to achieve the best bloom. A bright southern windowsill often works well. Most prefer intermediate temperatures of 55oF as the minimum for winter nights.
Good air movement, fresh breezes and fans, along with humidity above 50oF help to keep Oncidiums happy. To help achieve humidity in the home, a tray of water and stone under the orchid helps.
Oncidiums prefer lots of water and a regular feeding of 20-20-20 fertilizer at ¼ strength. Water about once per week, since the Oncidium needs to dry out. Never let them sit in water for that will decompose their fine root system.