As much as counterintuitive this may sound to a PWS, just notice how little effort speaking requires. No word or even most of the sentences require any conscious effort. And focus in your speech on the fluency of it, rather than disfluency - both do perpetuate the quality of the speech. Bonus tip - just focus on conveying the message rather than on your stuttering, and try not to plan your words in advance as this usually impacts how the message is delivered from a PWS