Most firewood is chopped by an axe or cut with a chainsaw, and it's more common in that process to eyeball the length rather than measure it. If your pieces end up dramatically different from each other, it will make bundling awkward.
If you plan on storing your firewood bundles inside your house, dry your wood outside first, so as to not create spots on your floor.
Create a 12-inch by 6-inch pile, being sure to include varying styles of wood into your bundle.
It's common to use stretch wrap as the main securing force around the wood, but a spot in the middle section needs to be left open, so the wood can air and cure over time.