Next you will need some scraps of lumber. Nothing too huge or beefy. I used some 1x2's that were left over from building our manger. I used a tape measure and pencil to mark them off into 24" lengths, or so. You will need four lengths of lumber.
Once your lumber is marked, grab up your best saw and trim them up. Arrange your cinder blocks so that the long sides are touching, and place each length of lumber in a hole, so that the bottom ends touch the inside edge of the hole.
rocket stove. That way I don't have to go searching for fuel the next time I get a hankering to do a project with it!