This page explains how I made this sourdough bread starter almost a year ago. (I live in eastern United States of America.) I am not an expert, but I have made a few rye starters in the past few years, and I like to experiment. I know that what I did here works, so I will share:

In a clean glass wide-mouth jar that is at least one quart and that was made in the USA (or had pickles or something with vinegar in it made in the USA) put in an equal mixture of bottled spring water and Hodgson Mills rye flour (I get mine at Harris Teeter grocery store).  Cover loosely.  Let sit at room temperature 24 hours.  It should have started to bubble by then.  Pour into it 1 cup of bottled water, stir, dump out all but one cup.  Add nearly 1 cup of flour again (to make a batter with the same consistency as you started with).  Pour into a clean jar and mark the height with a washable marker on the outside of the jar. Do this diluting and dumping and adding rye flour into a clean jar every 12 hours (I did mine morning and evening) until you have seen it rise to at least double and fall a couple times.  Now you are into the phase of getting it to smell very nice:  Refrigerate until morning.  Replentish as usual with water and rye flour and keep an eye on it.  When it starts to fall, put it in the refrigerator until the next morning.  Keep doing this until it smells nice.  Refrigerate 3 hours after "watering and feeding" the last time.  Please note:  It will smell horrible (a little like parmesian cheese) the 2nd and 3rd day, but that smell will gradually subside.  Feed and water it every week, even if you do not use it to make bread.  (I have also added raisins to begin with and then toss them after a few days.  The resulting starter had a different smell, and was nice, but for the trouble of digging out raisins, I do not think it is worth it.  I still maintain some of it in my refrigerator.) Never let starter get above 95 degrees because all the yeast will be killed.  Mine don't usually get above 80 degrees Farenheit.  Even when I bake bread, my dough is almost always between 72 and 80 degrees.  I have found that the lower temperatures make for a nicer smelling sourdough yeast and bread.  Thousands of yeasts are present, all with different smells, ready to grow, and temperature is a big factor in determining which ones will grow most and win.  If your starter ever gets a bad smell or very strange color, you must throw it out. (I am told pink is dangerous in a white flour starter.) This has never happened to me and it is actually unlikely because the natural bacteria acid and yeast are numerous and work together to not allow anything else to grow. But I have read it can happen, so always smell and examine your starter.  Starter will smell alcohalic, though, if it is not fed and watered often enough, and this is not dangerous, but the yeast will start to die. You may be able to save it by a new surge of daily water and rye feedings, or you may just want to start over. (hint: When you wash the jars, cold water at first works best, to clear out the visible batter.  Then use hot water, dishwashing liquid and rinse very well, and dry with a fresh clean towel. Some people sterilize their jars.  It is helpful to have two jars.  One clean and ready and one in use. Also a new wooden spoon handle reserved only for sourdough is nice for mixing with because it does not bang the jars and if you use it only for sourdough, you are not as likely to introduce any troublesome bacteria.) You may feed and water more often than once a week, as well, maybe even every day if you are using it up with daily baking and pancakes :) but please remember to feed and water at least every week. I do not recommend leaving for more than 2 weeks in the refrigerator unreplentished.