How to write

The writer must have eyes to see the vivid side of everything, as well as words to describe what he sees.  There is a cramping restriction of an insufficient vocabulary; not merely a loose and inexact apprehension of many words that are commonly used, and a consequent difficulty in using them accurately, but also a total ignorance of many other words, and an inability to use them at all; and these last are, as a rule, the very words which are absolutely necessary for the comprehension and expression of any thought that deals with something more than the most ordinary concrete notions.  

1. The connection between different sentences must be kept up by Adverbs used as Conjunctions, or by means of some other connecting words at the beginning of the sentence.

2. The connection between two long sentences or paragraphs sometimes requires a short intervening sentence showing the transition of thought.

3. Metaphor is briefer than literal statement.

“The cares and responsibilities of a sovereign often disturb his sleep,” is not as brief or eloquent as “Uneasy lies the head that wears a crown,” where the effect of care on the mind is assimilated to the effect of a heavy crown pressing on the head.

4. General terms are briefer, though less forcible, than particular terms.

General terms are briefer, though less forcible, than particular terms.  “He devours literature, no matter of what kind,” is shorter than, “Novels, poems or histories, no matter what, he devours them all.”

5. A phrase may sometimes be expressed by a word.

“These impressions can never be forgotten.”

“These impressions are indelible.”

Or

“The style of this book is of such a nature that it cannot be understood.”

“The book is unintelligible.”

The words “of such a nature that” are often unnecessarily inserted.

6. Participles may often be used as brief (though sometimes ambiguous) equivalents of phrases containing Conjunctions and Verbs. 

“Hearing (when he heard) this, he advanced.”

“Phrases containing (that contain) conjunctions.”

Sometimes the participle “being” is omitted.

7. Participles, Adjectives, Participial Adjectives, and Nouns may be used as equivalents for phrases containing the Relative.

“The never-ceasing wind,”

“The clamouring ocean,”

“The drenching rain,”

Inventing participial adjectives by adding -ing to a noun, is almost restricted to poetry.

8.  Conjunctions may be omitted, including adverbs, such as “very” or “so”. Also, avoid exaggerated epithets, such as “incalculable” or “unprecedented”.

The omission gives a certain forcible abruptness, “You say this: I (on the other hand) deny it.”

When sentences are short, conjunctions may be advantageously omitted.

Where a contrast is intended, the conjunction “but” usually prepares the way for the second of the two contrasted terms: “He is good but dull.”

9. Apposition may be used, so as to convert two sentences into one.

“We visited the house of a person to whom we were eager to meet, a musician, and, what is more, a good friend to all young students of music.” 

10. Condensation may be effected by not repeating (1) the common Subject of several Verbs; (2) the common Object of several Verbs or Prepositions.

Brevity often clashes with clearness. Let clearness be the first consideration.

How To Write Clearly - Part 1

How to Write Clearly - Part 2

Source: ABBOTT, EDWIN A., M.A., HOW TO WRITE CLEARLY - RULES AND EXERCISES ON ENGLISH COMPOSITION.