[git] How do I simply create a patch from my latest git commit?

I'm looking for the magic command of creating a patch from the last commit made.

My workflow sometimes looks like this

vi some.txt
git add some.txt
git commit -m "some change"

and now I just want to write

git create-patch-from-last-commit-to-file SOME-PATCH0001.patch

but what should i put there instead of create-patch-from-last-commit-to-file?