It amazes me how many people promoting themselves as authors and writers post blogs and messages littered with misspelled words. The occasional grammar slipup can be excused, as long as it is rather obscure and not glaring. But using the wrong word or leaving misspelled words seriously damages your credibility as a professional.
It only takes a few moments to proofread and spellcheck a document. Take the time.
Spend a few moments learning commonly misused words. They're, there, and their; insure and ensure; and others. With online dictionaries, it's a snap to check the meaning of the word you are using. Do it.
Please, for the sake of communication, learn to do it right; especially if you call yourself a professional.