The best advice that I can give you is...do it more!
The best way to improve your writing is to write.
As for reading...yes...read more. When I say read or write more...I mean EVERYDAY.
If you want some ideas for what you can do check out this article How to Study English: Top 20 activities to do daily to learn English
That is all you need to do. Practise and it will get better after time and dedication.
Student or Learner