These can be really tricky to make right so that they work properly. It needs a piece of carbon felt between the inner strip wall, and the outer can wall to act as a wick for the jets. It would be inserted at Step 9, right there where the first picture is. I could never get one to work right myself, they always seemed to leak. So I got a Trangia. I know it is heavier, and I didn't make it, but it was at a Goodwill for a buck and it can save fuel in the stove with a sealed lid.