If you’re baking regularly, like weekly, make sure to feed it after using the amount called for in your recipe before returning it to your refrigerator. 

• When you feed your starter, feed it with approximately equal weights of flour and water. About 3/4 cup of spring water for every cup of unbleached flour.
• The amount you feed your sourdough starter depends on how much of it you have to start with. You want to double the amount of starter you have each time you feed it. However, if you already have a couple cups of starter on hand and typically use much less in your recipe, it doesn’t make sense to double the existing two cups of starter. In this case just discard of a cup or more of the starter and then double what remains. (You don’t really have to throw it away, – try my Sourdough Pancakes, Sourdough Soft Pretzels, and Sourdough Pizza Crust– a great way to use a lot of starter quickly).
• If it has been a long time since you’ve fed your starter and you don’t plan on baking for a while, don’t feel like you have to go through a big rigamarole to keep it happy, just stir in a 1/2 cup of flour and about the same amount of water and forget about it. That will at least buy you some more time before you have to worry about it again.
• If you need a whole wheat or rye starter, it’s easy to convert your white flour starter by just a few successive feedings with the flour you want. You may have to adjust the water as some flours are thirstier than others.
• Be sure to store your starter in a container that’s not airtight. If you’re using a wire bail jar to store your starter, just don’t use the rubber gasket that comes with them.
• When you need to use your starter, you can use it straight from the fridge or let it come to room temp first if you want. If you use it straight from the fridge, it will just add a few minutes to your dough rising time.
• After you feed your starter, you can let it sit out for several hours before returning it to the fridge or put it in the fridge right after feeding it.
• If you really don’t think you’re going to use your starter at all for a very long time, (some people don’t bake during the summer, for example), you could dry some starter and freeze it. It will store this way indefinitely. Then revive it in the fall. 

A healthy starter rises well in its container and becomes bubbly and spongy after a good feeding. It actually looks like a sponge after a few hours of feeding!

Refer to my Homemade Sourdough Bread to bake your first loaf! Enjoy!