Actually, there's no need for tears at all, it's a doddle making your own kefir, but why waste a good title?

How to make your own kefir

The first thing you need are some kefir grains, which are little clusters of culture (bacterial, not Proust-reading). If you can't find someone with spares to give you they're easily and cheaply bought as mail order on t'internet.

If you buy them, the grains will come with instructions, which will be variations on the theme of "put the grains in milk and wait".

There are only two rules

Kefir grains don't like contact with metal
Kefir grains don't like contact with chlorinated water, but I'm not sure why you'd want to do that.
So it's just rule 1 really. No metal

Put your kefir grains in milk - but don't get stressy

When I started making kefir I was a bit precious and only used full fat organic milk, preferably raw, but actually they seem just as happy in semi skimmed from the milkman, the choice is yours. Other liquids you can similarly ferment with the grains, but I've stuck with milk.

I've used different containers, but ended up with a drinking glass (for ease of washing up), and making a jaunty hat from a coffee filter and an elastic band. I use about 1/2 pint of milk.

Leave the jar of milk and grains at room temperature for around 24 hours, maybe giving it a little stir with the end of a wooden spoon, and, bingo, you've done it. You're practically from the Caucuses. Do not worry if there is separation, that's fine.

If your kitchen is particularly chilly you might want to find a warmer spot, I put mine on the boiler (which is well insulated, so just slightly warm) in the winter. Mostly it just sits on a work surface though.

Sieve.

You now want to retrieve the grains. The method I've landed at is to place a plastic sieve in a cereal bowl and tip the contents of your kefir glass in the sieve. Swill and jiggle it about in the bowl until all you have in the sieve are the grains.

Plonk the grains in another glass, add milk, pop its hat on and off you go again, ready to repeat every day.

The grains will increase, so either donate any spare to a friend or dispose of them.

What's kefir like?

The kefir I make varies a bit each day, but essentially it's like a runny yoghurt. sometime with a bit of fizz. I tend to use it as a breakfast, with nuts and seeds and fruit added. It's also lovely as a drink with a square of chopped up chocolate, some chia seeds and a good shake of cinnamon and maybe some finely chopped mint leaves.

The only limit is your imagination (or Pinterest)

Make it stop!

If you need to cease production for a while, pop the grains in some fresh milk and store it in the fridge.

If you're inspired to ferment more, here's my easy kimchi recipe.