Your prose fiction text should have a good narrative balance. That is, a good balance of: description, dialogue, action, inner monologue and exposition. The balance shifts a little in different genres: mass market / genre fiction may have more dialogue and action, whilst a more literary text may have more reflection and description.
Exposition is a little out of fashion at the moment. This involves “telling” instead of “showing” and can be boring for the reader. Can you tell your reader any back story or anything about an alternative world by putting the words into a context?
In all cases, no one narrative element should take up more than a page at a time.
Description
We need less of that now than we did in Dickens’ time. Then people in the country didn't know what it was like in the town. Indeed, even people who lived in Bolton may have been astounded by Manchester. These days a little description goes a long way. Tell us about a pub having a patterned carpet and we immediately know a lot more about it. On the other hand writing with the senses always produces excellent writing. What do you or your character see, hear, smell, feel (in both senses) or taste? We tend to get stuck on the visual. Try using the other senses.
Dialogue
This is one of the most effective ways of showing us character. It can also push the plot forward and help to create atmosphere. However, avoid using it deliberately for exposition or back story. Would your characters actually have that conversation if you weren’t there?
Action
Short, sharp sentences can increase the pace. Avoid using adverbs and use a more effective verb. E.g. ‘he ran’ instead of ‘he moved quickly’ ‘he gobbled his dinner up’ instead of ‘he ate his dinner quickly' or ‘she clattered around in the kitchen’ instead of ‘she worked noisily in the kitchen’.
Inner monologue
Get right into your character’s head. Avoid using “thought”; that immediately puts up a barrier between your character and your reader. So: ‘Would he be back in time?’ instead of ‘"Will he be back in time?" she thought.’ Not even ‘"Would he be back in time?" she thought,’ as, if we are already in her point of view, we know that it is she who is thinking.
Exposition
If you really need to tell your readers something about a world you’re creating think very carefully about how you do this. For example, don’t say ‘On the planet Zog the rain was so acidic that it cut through anything that was unprotected.’ Try 'Zenny bit his lip. They’d been too late covering the carts. The rain was now eating through it. He could only watch as the vehicles fell to pieces.’
