“Writing is an instrument for conveying ideas from one mind to another; your job as a writer is to make the reader grasp your meaning readily and precisely.”
Source: Gowers, Plain Words
To write well – as with any skill – purposeful practice, in areas of weakness, consistently over time, will lead to improvement.
“The final cause of speech is to get an idea as exactly as possible out of one mind into another.
Its formal cause therefore is such choice and disposition of words as will achieve this end most economically.”
Source: G. M. Young, Last Essays, 1950