Cut strips of fabric that are just over half an inch wide (if you are using the cooling rack I used - if you are using a different one measure the space between each row).
You will need strips in the following colors/lengths: Blue: eight (9 inch) strips. White: three (9 inch) strips and three (15 inch) strips. Red: five (9 inch) strips and four (15 inch) strips.
Begin weaving in the blue strips at the top left, going over and under each wire. Go close to halfway across.
Weave in eight blue strips, alternating which wires you go over and under. Then flip the cooling rack over, fold the strips over and secure with hot glue. Note that some of the strips will go over two wires in a row at the left side of the section and some strips will go over two wires in a row at the right side of the section.
Starting below the blue section, weave in the longer strips of white and red. The bottom two rows will both be red. Then weave in the shorter strips of white and red. The top two rows will both be red.
Flip the cooling rack over and secure all the strips with hot glue. The shorter strips of red and white will get glued behind the blue section.
Finish the flag by embellishing as desired: I used one wood star tied with some twine, but you could use multiple stars, or bows, ribbons, etc.