1) Write more (non-optional advice )
2) Read "Elements of Style"
3) Learn from good articles. Does any article cross your mind as you read this?By far the most engaging post I have ever read:
Four little things that shaped India: Part 1 | The Kaipullai's Vetti Thoughts : The outer playground of my inner devil
4) Find a style of writing which suits you and keep working on it.
A tip from Joe(the disciple of Po) - If you want to get paid to improve your hand writing you can start off with constant content.