From existing milk kefir (I prefer this):

1. Follow the directions on the package of milk kefir starter culture grains. You’ll just be dumping the culture contents into 4 cups of milk and letting it thicken. For me, this took 24 hours the first time. After the milk thickens, you’ll have kefir you can consume and make more kefir with. Store this kefir in the fridge until you’re ready to make more. 
2. When you need more kefir, take 1/4 cup of the existing kefir (always save some from previous batches) and pour it into a clean, glass jar. 
3. Add the desired amount of milk and mix with a wooden spoon. 
4. Cover the jar with the coffee filter and secure with a rubber band. 
5. Let this ferment and thicken in a cozy, dry place (I choose the corner next to my stove because it’s warmer) for 12-18 hours. When it’s thick, it’s done. 
6. Place a lid on the kefir and store it in the fridge for a week or so. Always remember to save at least 1/4 of the batch for the next one. 

From milk kefir grains:

1. You’ll first need to hydrate your kefir grains if you’re using dried. Follow the directions on the package you’re using, or pour the kefir grains into a glass jar and add a cup of milk. Cover with a coffee filter and secure with a rubber band. After 3-7 days, they’ll be hydrated. 
2. When you have hydrated grains and are ready to make kefir, strain the kefir grains out of the milk they were hydrated in and place them in a clean, glass jar. 
3. Add the milk and mix with a wooden spoon. 
4. Cover the jar with the coffee filter and secure with a rubber band. 
5. Let this ferment and thicken in a cozy, dry place (I choose the corner next to my stove because it’s warmer) for 12-18 hours. When it’s thick, it’s done. 
6. Strain out the kefir grains and repeat steps 2-5 again. Place a lid on the finished kefir and store it in the fridge for a week or so. As you can see, with this method, you’ll always be fermenting kefir because the grains need to stay hydrated.