Occasionally, for whatever reason, I'll look up and realize I was supposed to write 600 words and I've written 900, so I need to cut it down. Here's what I do when I need to prune back pieces. As always, your mileage may vary.
Look for sentences that say the same thing in different words. My personal tendency is to do this at the beginnings of things. Despite history, I start just about every piece convinced that I can't possibly wring 500 words out of a topic, so I start out generous with words. If I'm going to repeat myself, it generally happens in the introduction. Cutting out redundant sentences can get your word count down.
Search for adverbs. Getting by without adverbs would most likely be impossible, but it's easy to rely on them too much. Since so many adverbs end in "-ly," you can use Word to search for that combination. Then you can go through and see which adverbs can be deleted without taking anything from the narrative. Some adverbs can be eliminated by choosing a better verb than the one you've paired it with. My personal experience is that the word "very" is hardly ever necessary if you've worded things with care.
Go back and re-read the client instructions. Maybe you've included a whole paragraph on a subtopic the client didn't ask for. Could it be deleted altogether? Could it be significantly shortened or reworked as a single sentence in another paragraph? The answer is usually, "Yes."
Let it sit. My rule of thumb is to let pieces sit for at least several hours before doing a final edit, proofread, and submission. Getting your brain out of your work for a while lets you come back to it with a fresh perspective and see extraneous words, phrases, and sentences you might not have seen otherwise.
Try these tips for pruning and shaping your prose, and you'll find it easier to get your pieces to the right length for the client, and you should end up with leaner, cleaner work too.
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