This author, Catherine Coulter, was funny and to the point. She talked about being uncluttered in your writing, such as using more nouns and verbs, avoid the -ly adverbs (there are better ways to say them), swear words and gratuitous sex scenes can be eliminated if they don't have a purpose. Express the feelings of the characters to give them a third dimension to the reader.
Detailed gore isn't needed in a murder story unless you are writing classical horror.
Do more 'telling' and less showing. Dialog helps move the story along. Too much narrative can become boring and lose your reader. Keep away from cliches and oddly spoken descriptions.
Don't make your characters perfect. They will come off looking like cartoons.
Keep in mind if you wouldn't say something aloud, then don't write it.
Cut the adverbs, especially the -ly words. and adjectives that aren't real, such as "his steel-tight muscles."
Using 'said' doesn't carry emotion or judgement. Don't use 'wailed, raged, giggled, etc," these are not synonyms for SAID.
She recommended the book "Strunk & White's Elements of Style." - I love reading her stories, they are fast paced without too much repetition. The quoted parts are from her handout, the rest I have paraphrased my notes from the class - A Nation.