Then I put in some fallen leaves. I did this in November, so it was easy to find leaves, however if you do this when there few fallen leaves you can use fresh leaves. Just make sure you have a selection of different types, and not too many evergreen as these are tougher.
Then I put some moss. This is not really necessary, but there was some lying around that the blackbirds had hauled out whilst looking for insects, so I used it.
Next I poured in some water. I pured it is slowly and waited to let it trickle down before pouring in more. I stopped when the wetness had reached the bottom.
Finally put in the worms. They will start to tunnel within minutes, especially if it is a sunny day.
Now all you need to do is cover the sides with dark material, or you can push the whole thing in between two bookshelves. The worms will tunnel away from the light, so if you don't do this you will not see their tunnels.
Then once a week have a look at what they've been up to. Even better is to take a photograph and compare the progress.
Every now and then some more leaves can be added, and some water gently poured on top.