Blogging is more about you writing your experiences than what readers want to read. To get the right audience, follow your heart and write what you actually go through.
Grammar - Depending on the language you use, blogging just makes it imperative that you are reasonably good with your grammar skills and proficiency if not a master. Remember your audience is a mix of both; the ones who are experts and the ones who are not.
Focus on good content, not on monetization. Over time, money and benefits will follow good content.