How do you spell better it out?

"Better it out" is not a common phrase or idiom. It's possible you meant:

* "Spell it out": This means to explain something in detail, using clear and simple language.

* "Better it out": This could be a mispronunciation of "better eat out," meaning to eat at a restaurant instead of at home.

Please provide more context or clarify what you're trying to say.