Good, and the way to tell if you have good fermentation is to see if there is a clear seperation between the curds and whey. The whey is an opaque liquid and the curds are thick. You can also take a sniff and see how things are progressing. What you should be smelling for good fermentation is a vinegary smell. That comes from the Aceter bacteria that are the last to get into the action in fermenting Kefir. So, it might be anywhere from 24 to 48 hours depending on temperature, elevation and type of milk. You can blend rice/almond and cow milk to make a mixed Kefir as well.
Originally Posted by breadsauce
And then, once strained, the Kefir should sit for another two to three days in the fridge. And you might have to drink small amounts until your body gets colonized and used to the kefir culture.
Here's a good site for all things about kefir: