'There is no line of my verse or prose which has not been mouthed till
the tongue has made all smooth, and memory, after many recitals, has
mechanically skipped the grosser superfluities'
Rudyard Kipling, Something of Myself, New York: Doubleday, Doran & Company, Inc., 1937, p 223.
If you feel the rhythm of a piece of writing doesn't work, you will automatically have an instinctive idea of what element isn't working. You'll feel instinctively whether a phrase needs to build more, to have more suspense. You'll know whether a word is just one or two syllables too long. You'll know whether something needs to be stretched out or whether it needs to be contracted. You'll know whether something suddenly changes from duple metre to triple metre unexpectedly and jarringly.
As soon as you've defined what the problem is, it will be easier for you to fix it.
As Kipling (who is a master of rhythmical writing) notes, reading aloud is key - and doing so repeatedly really helps.
It sounds like you may need to break the elements of rhythmic writing down more precisely, working from the basic elements of vowels and consonants upwards to words, phrases, clauses, sentences, paragraphs and larger sections.
It's hard to gauge the familiarity and skill level you have, but books on the elements that I've found useful are:
- Ezra Pound's ABC of Reading
- Geoffrey Leech's A Linguistic Guide to
English Poetry and
- Geoffrey Leech and Mick Short's Style in
Fiction: A Linguistic Introduction to English Fictional Prose