Its pretty basic Don't waste your money on that doc.
Search the forum and others for people's methods there is some variety.
1.Get box, line with styrofoam.
2.Put in either cotton stuffing (filter floss), newspaper, shredded paper, packing peanuts, etc to fill in space.
3.Put fish/inverts in a breather bag or regular bag. Breather bags are the new trend and work very well, it's basically a "smart bag" that lets CO2 out and O2 in, the membrane breathes somehow
. Tundragirl just ordered a big batch of them and I got some from her I got around 50 for $15 shipped, Maybe more can't remember, but it was a good deal.
4. If adding heat/cold pack tape to the top or side of the container and make sure it is not touching the bag with the contents in it because it will be too hot.
5. Tape box up good and bring it to your LPO, send and repeat.
Thats a very simple method and very bland, searching more will result in more detailed results specific to your items. Remember catfish are spiny, and so are larger crays.