At the heart of bokashi composting is the microbe laced bran that you use to inoculate and thus pickle your food wastes. It's pretty easy to get this bran online but it's also easy to make a batch up for yourself - and doing it yourself naturally saves money.
To make your own you need these ingredients.
When I was working with my town we made this demo video about how to make your own bokashi bran.
Dissolve the molasses in the water. Add the EM microbes. Put the bran in a container big enough to hold it. Add the liquid and stir it up well with your hands. The mixture should be damp enough to hold together when you squeeze it into a ball but not so wet liquid is dripping from it. Adjust the moisture by adding either a bit more liquid or more bran.
Put the damp bran into an airtight container.A dark garbage bag in fine. Squeeze out all the air and fasten the top securely. Let it sit in a warm place out of the way for a minimum of two weeks. It's okay to leave it longer.
There may be some white mold on the fermented bran at the end of the two weeks. This is good. If however the mold is black or green it means either some air got in or the material was too wet.
For storing long term dry the bran well. Ten pounds of bokashi would last the average family 6-10 months. Properly dried it can be stored for several years. Store in an airtight container out of direct light.
You might decide to get together with friends and make a big batch at once. Here are the amounts you need to make 50 pounds of the bran. For a family this would be enough for several years.
Use the same method as above. The water needed will depend to some extent on where you live. If it is very humid you will likely need less water, very dry more water. Test by squeezing a handful of the bokashi together.
For long term storage dry and then store in airtight containers out of direct sunlight.
I just spoke with the local feed store here and can get a 25 kg or about 55 lb bag of bran for $20. I can buy a liter of microbes from a Canadian supplier for about $30. I only need $6 worth for my bran. The rest I can store for later batches. I figure I can make a 3 to 4 year supply of bokashi for about $28.
For premade bokashi I would pay about $15 for 5 pounds from one supplier.
Your bran and molasses are available either at the grocery store or at a feed store if you live in an agricultural area. Water comes from the tap left to sit out for a couple of days. The only tricky ingredient is the EM-1, effective microorganisms or something equivalent. As microbes can not always pass borders easily you need to find a source for your country.
For the United States EM-1 is available though Teraganix
Canadians can order an EM equivalent product at The Organic Gardener's Pantry.
If you are from another country contact EMRO Japan to find a source for your area.