Depending on the temperature of your kitchen, humidity of your climate and many other mysterious factors, the sauerkraut will take anywhere from 3 days to a week or more to ferment and reach that tangy flavor. Check it once daily to see how it is coming along. You can allow it to continue fermenting even after it achieves that classic flavor, but the first few times you experiment, you may want to quit while you're ahead to avoid ruining the batch and discouraging yourself.
Don't be thrown off by the aroma either! That funky, sulphuric smell means that fermentation is happening, you're moving in the right direction! You'll also see a greyish mold will form over the very top. This is normal, and quite harmless, but try to remove most of it before eating.