Build former F4 up. The front of former F4 consists of 4 parts. The top middle part has 2 holes that do Not pass through the paper on the other side. Remove the foam only from the holes, leaving the paper on the back side. Glue in 2 8mm neodymium magnets, one at a time so they don’t come out and stick to each other. Then flip the part with the magnets over and glue it with the paper side up so the magnets are concealed, onto the larger F4 former part. Glue on all remaining parts as shown in photos.