Here is a good website with information about water kefir grains (YCK is essentially water kefir): http://www.wholetraditions.com/articles/3-water-kefir-instructions .
This is how I keep mine alive in between culturing coconut water: http://www.lifeisapalindrome.com/recipes/how-keep-your-water-kefir-grai…
Also, Rebecca recommends:
--Dom’s kefir making: http://users.chariot.net.au/~dna/kefirpage.html#alternativekefir
--A very detailed list of frequently asked questions: http://www.yemoos.com/faqwamain.html
--A nice video tutorial: http://zoevblog.com/2010/03/17/what-is-water-kefir-and-how-to-make-it/
3 young Thai coconuts
1 packet Body Ecology Diet kefir starter https://shop.bodyecology.com/prodinfo.asp?number=BE010 , OR 6 tbsp. kefir from your last batch made with BED starter, OR 1 tbsp. water kefir grains
First, open the coconuts. This is very intimidating the first couple times, but isn't too difficult and you can google for video tutorials. Basically, you whack the heel of a chef's knife around the top (pointy) end of the coconut, until you can pull out the resulting center "lid" piece.
Pour the coconut water through a fine sieve into a jar (you'll get about 4 cups).
Next, follow the instructions for the powdered starter, or for using the last batch's kefir as a starter, OR, mix your water kefir grains with the coconut water.
No matter what your starter type, your kefir will need to ferment at room temperature for several days. I let mine go for three days, till it's almost fizzy, very tangy, with no traces of sweetness left. Sometimes there's a little scum on the top, but I haven't found that this affects quality--I just scoop it off.
Start slow! The probiotic combo of good bacteria _and_ yeasts makes this stuff powerful. Now we have 2 tbsp. per meal, but we started drinking 1/2 tsp. every other day.