Most of us think effective writing is about grammar, punctuation, and spelling. That’s not true.lear: Write in a way that people always understand what you’re saying. Clear writing only has one interpretation. That’s what makes it effective. Credible: You can’t make the reader believe you. Your reader only believes you if you write credibly. Know what you’re talking about. If you ramble or are dishonest, a reader will sense it immediately.