I admit it takes a long time for me to compose anything in English. Sometimes, a posting on this blog will require 2 hours. I was never coherent in my thoughts and thus found it very hard to concentrate my ideas, if there are any at all, into consistent sentences.
Constipation.
Remember the principles of good English writing that we were once thought in school? Simple and concise but not monotonous. Straight to the point. Use jargons only when needed and use simple words for all else. Create good form and structure in your paragraphs. While the 'rules' are simple, it's certainly not simple for some individuals.
Anyway, I found an online article Elements of Style that may be quite useful for those who have similar problems like I do.