Any and all authors are encouraged to give input here. I'm sorta mixing advice for critics, and giving constructive criticism so bear with me.
So "How to write constructive criticism", or alternatively "How do you become a good critic"....ironically written by a novice in both categories. ;)
1.) READ DIVERSELY! I think the #1 rule to giving good reviews, critiques, and advice is that the more well read you are, the better. Read a large variety of novels and poems across a broad spectrum of genres so that you can better analyze someone's writing style, and the elements within a particular genre. Critiques are like anything else; the more knowledgable you are in an area, the more ability you have to judge a work.
2.) Critique objectively. Just because you don't like murder mysteries does not make the novel poor. Try to judge a work under the natural category or genre. This can be a lot harder said than done, especially if you are not accustomed to reviewing under different genres.
3.) Be specific in your complaints or your praises. Give an opinion with a strong basis for having one, and use specific examples from the text you are reviewing. Highlight issues upon which the writer can clearly see, and follow your train of thought. If the author cannot understand where you are coming from or how to improve based on your advice, you are not being constructive. Be as detailed as possible in reviewing the work as a whole, specific elements, and both major and minor issues you find with the work.
4.) Make sure the objective of your review is to improve the quality of the work. Anything said about a work should be designed with an improved version in mind. If the author cannot come away with improvement methods or ideas from your review, your review is garbage. A good critic will be able to influence what an author does in the future; If your criticism is taken and lowers the quality of the work or the author, you are not giving good advice or constructive criticism. The best policy here is to simply ask, "Would I take my own advice if I were a writer?". If not, change your criticism.
5.) Harsh does not mean good. There is a tendency for some critics to be excessively hard and nitpicky, which does not necessarily correspond to constructive or helpful. Even bad works have good moments, so it is important to highlight what you feel an author does RIGHT just as much as what an author does WRONG. The opposite of this is also true, lenient does not mean good. I am guesing authors generally find it is harder to get good and constructive criticism from family or friends than it is to get praise.
6.) State your POV. Authors write for an audience, as do critics. It is important to state to the author where you feel your criticisms stand. Whether you are reading from a specialized or specific POV, eg someone who only reads certain genres, or you feel you are reviewing on behalf of everyone it is important to make sure you are addressing your starting position. If you don't read poetry or write poetry, state so. The poet can then see you represent people that are new to poetry. The Harry Potter series is popular to kids as well as adults; good critics will comment on these works as "fun for everyone", bad critics will comment on them as "children's books". Whether you recommend one read the work or one not waste money on it does depend on the audience you feel the work is geared towards.
This is something you can see in movies especially. Critics may rate a movie low and tell you "don't waste your money", but the movie can end up being a cult classic, or wildly popular. This can be because the critic is looking through a different lens than the average movie goer.
7.) Avoid simple scoring. Whether this is letter grade, numerically, or other, judging something complex like a poem or novel with a simple grade grossly misguides the work and underrepresents it.
8.) It is easier to be critical than correct, a great man once said. You are not a weatherman. Being wrong about a review is not a way to win an audience or reputation as a trustworthy critic. Works you review favorably should show; they will win awards and reach a large audience. Works you review poorly should show as well; they will not be thought of highly by anyone else. While you should have an independent opinion, you should know what other people think about the work as well; if most people disagree with you there will more than likely be good reason and cause for it.
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Brief survey of what I feel good critics do, and what good criticism and reviews look like. I encourage people to add their own, or comment on the ones listed above. Agree, disagree. An informal Q&A if you will. I will compile the results once all is said and done.
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