How do you keep one alive?

Light?
Water how often?
Soil?
Temp?

Keep your Rubber tree (Ficus) in average home temps. Minimum at night should not be less than 62 -65 degrees. They do well in diffused sunlight or partial shade such as a well lit spot in the room out of direct sun or with a sheer curtain between your plant and the sun. Water you plant when it starts to feel a bit dry. Don't let it dry out completely. Don't repot unless you have roots hanging out the bottom. Then put in a rich potting soil such as an African violet soil. Fertilize at half strength with a standard water soluble houseplant fertilizer every two months. Hope this helps.