How do you kill a bird?

1. Take a Knife
2. Grab the bird
3. Fold the bird tight
4. Take the knife and stab it (stab it real hard)

I don't know why you are asking this, but ideally:

1) take it to a vet to me humanely euthanised.

2) if you are killing it to eat it, such as a chicken, firmly hold the neck and head in your two hands and sharply and swiftly twist forcefully to quickly kill it with minimal pain.

3) Don't kill a bird just for the heck of it.