How do you write I not speak Spanish?

The most natural and straightforward way to say "I don't speak Spanish" in Spanish is:

"No hablo español."

Here's a breakdown:

* No: This is the Spanish word for "no".

* Hablo: This is the first-person singular present tense form of the verb "hablar" (to speak).

* Español: This is the Spanish word for "Spanish".

You can also use a slightly more formal, but still correct, version:

"Yo no hablo español."

This adds "Yo" (I) at the beginning of the sentence for emphasis.