Writing dialog for spanish speaker.

[jfields]

Do you mean that you're a Spanish speaker who is having trouble writing dialogue?
Or that you want to convey that someone is a Spanish speaker in your story?

Usually that's done by replacing some English words with Spanish words that are unmistakable in context. But be sure your character reflects the culture he is from in all ways -- if he's Spanish speaking, he was probably born outside the US. How might that result in a different viewpoint? Different way of dealing with people? Different responses to the situations he/she comes into contact with. Those things will also reflect in the dialogue for a main/important character even though the dialogue is written in English.

Or if the person is only part of the story briefly and only speaks a few lines, you can actually do the lines in Spanish and make whomever understands the Spanish either translate for others or translate in his own head. I've seen it done that way as well.