
Julie C. answered 03/24/19
Certified English/ Reading Teacher
One easy and free tool you might use is Grammarly (www.grammarly.com). It will correct any obvious grammatical errors with your writing for free and, if you pay for a subscription, will also offer more high level grammar editing (like wordiness and run on sentences). You can install it on your internet browser and it will correct your writing as you type.
Another great online resource is www.noredink.com. It's free version offers diagnostic assessments, grammar lessons, practice and quizzes to check for growth. It's made to be a teaching tool for educators, but you could also use it to teach yourself mastery over various aspects of English grammar.
If you're interested in a guided tutorial of either of these platforms, let me know!