As a teacher, I was often asked by parents how they could help their children's writing skills and my answer would invariably be to foster a love of reading at a very early age. Lead by example, I would say. Children who see their parents enjoying a good book are likely to be more inclined to read themselves. Sadly, all too often adults would tell me they enjoyed reading but didn't really have the time. Confident readers usually make more confident writers, and confident writers have a greater chance of success in their working lives.
Careful proof-reading of written work can help rectify mistakes and give the final polish needed to any form of written communication. Students invariably dislike proof-reading, so why should busy working adults be any different? Yet the importance of accurate writing cannot be stressed enough, and a reputable grammar checker and proof-reading service is invaluable. Grammarly told me:
"We proofread 400+ freelancer profiles from all eight categories of the Elance platform for grammar, spelling, and punctuation errors. To adjust for quality of work, we only selected freelancers with an average rating of four stars or above. We then looked at correlation between earnings and number of mistakes. We hope the direction the data is pointing in spurs some thought and conversation about the importance of good writing."
Grammarly's infographic elaborates on their findings: