Razor knife, cardboard boxes, and two types of packing tape, the 2 inch wide thin stuff, and the fiberglass reinforced stuff.
Strips of cardboard, folded and taped over the ends, then a wrap or two around the whole lot, lots of tape. Mummify the package, add a couple layers of reinforced tape across the ends, and then mummify those again.
I figure the rule of thumb is that if I do not trust the packaging to withstand being hurled against a cinderblock wall, by a PO'd Postie, it is not well enough packaged.