You can prepare for disaster by buying lots of canned soup. Or you can buy this bow.
It sets up in minutes: just insert the two fiberglass-resin limbs into the brackets mounted on the riser and voilà, you have a weapon ideal for hunting small game or, you know, defending yourself against the Walking Dead. Choose from 35-, 45-, and 55-pound draws, and it works for both left- and right-handed users.
The setup includes three arrows, but you'll likely want a couple more, just in case.