You will need to find a large glass jar with straight edges. Glass so you can see what it's doing, straight edges so it can climb as it grows. A gallon jar is good because there's more surface area but a bit smaller is okay.

You'll need a sharpie for marking the side of the jar from day to day.

You'll need another smaller jar for permanent storage in your refrigerator.

Ingredients

If you can get some dark rye flour or pumpernickel grind flour for the seed culture it makes for a more complex flavored barm but it isn't necessary. Many places carry this in their bulk bins and you'll only need a cup's worth. Whole wheat or a high protein bread flour is a perfectly acceptable substitute. You will need a 5 pound sack of high-protein bread flour to complete the barm.