Please let the writer know what they have done well, preferably before you critique! It is both considerate and will also make them more likely to listen to your advice. Positive feedback is just as important as criticism because it lets the writer know what not to change. Constructive criticism shouldn't be hurtful if it contains both positive and negative feedback.
Look for anything that doesn’t make sense or is unclear.
Paragraphs/sentences/phrases/words that feel jarring and/or pull you out of the story.
a) This could include anything that breaks the sentence flow:
• Awkward wording.
• Details mentioned in the wrong place or time.
• Words/expressions that are too “Earth,” that pull you out of the fiction world by reminding you too strongly of the real one.
Redundancy and over-explanation. (If the writer is insulting your intelligence, tell them.)
Look for sections that are too slow and drag.
a) Any area that seems:
• Boring / Uninteresting
• Unnecessary / Insignificant
Conversely, look for sections that pass too swiftly. Let the writer know what you want to know more about, and what you wished they had spent more time on.
If something about the overall prose bothers you, then mention that as well. They may not be able to radically change the way they write, but they would probably like to know what irks readers about their style.
a) Let the writer know what you find excessive/what you think they can improve on, such as:
• Too many or too few adjectives.
• Too many adverbs.
• Too many weak verbs. (Ex: “Bob was walking” versus “Bob walked”)
• Too much descriptive language or too little descriptive language.
• One word repeated too many times too close together or an often repeated/cliché phrase that is impeding more successful description.
Think about believability. Not in regard to the real world, but in regard to the rules and limitations of the fictional world the writer has created.
a) Also pay attention to believability in:
• Character development. If a villain suddenly becomes a saintly philanthropist, or a three-dimensional flawed character acts like a Mary Sue, that would be unbelievable.
• Progression of dialog.
• Setting. If you notice that some plant/animal doesn’t belong in the environment or season it's been placed in, the weather seems strange, or some geology is not where it should be, let them know. This goes back to #2 above.
Look for grammar mistakes, but don't be a stickler. Just make sure that the grammar choices are intentional and serve the narrative.
