Welcome to the new orchid varieties such as the Phalaenopsis or moth orchids that are much easier to grow than in the past. First do not overwater. That is the most common reason for orchid death. Poke a finger or toothpick down one inch into the bark or moss. (Orchids should not be planted into soil.) When the growing medium is dry to the touch or when a toothpick comes up still light in color you can water by sitting a potted orchid in sink and allowing a cup  or so of water to rush into top of soil and out of drainage holes. Do not let orchids sit in standing water. If in doubt, do not water. Better to underwater than overwater. Do not get foliage or center of plant wet if you can help it. Second most orchids prefer 4 hours of bright light - but will sunburn in direct sun. So an East facing window is great. Third, orchids are not heavy feeders. Do not feed at all while they are blooming. I use only one half teaspoon of Osmocote around each orchid plant once a year when the plants are done blooming. They need all the micronutrients that a complete fertilizer like Osmocote supplies. They do not like a high nitrogen plant food - that is the type usually sold for house plants. Too much nitrogen means all leaves and no flowers. Now to get an orchid to rebloom keep in mind that lower night temps is what triggers bud formation. Leave them near a window or in a room that is cool at night. 50 to 60 degrees at night and above 65 during the day works for my plants. You can also cut back the stem that held the old blooms as  this can stimulate a new flowering spike to form. Experiment, observe and have fun figuring out what growing conditions you need to provide in your area with your orchids. Gardening is an adventure that keeps you growing, Marianne Binetti