Unclear grammar confuses readers. Learn your grammar, practice, and improve before breaking convention. Spell checkers help, but they are only the first step to the editing process. Keep the holy trinity of reference books nearby--dictionary, thesaurus, and "Chicago Manual of Style"--and use them. "The Elements of Style" is a classic useful for tightening your writing. Then there are other entertaining grammar books like "Eats, Shoots & Leaves" that can help clarify the messy and ever evolving English language.