The basic and primary rule of a good paragraph is to focus on one idea and build supporting sentences around that one topic. First, choose a key sentence to define the gist of the paragraph. For example, if you wanted to explain how to groom a Persian cat, the central paragraph idea would be, "Grooming a Persian cat is not difficult but you must have the correct equipment." Support this thesis with developing lines such as "You need fluffy towels, shampoo and a hair dryer that has a low heat setting." Do not leave the main topic by writing unrelated sentences such as "Persian cats, especially the Peke-face Red Persians, have a greater risk of respiratory disorders because of their flat faces." Use these unrelated arguments for a separate paragraph to maintain linearity and to create consistency in the manuscript.
Narrative consistency, like focusing on one topic, is an important building block of a paragraph. Do not write sentences that fail to connect with following sentences. Writing "Shampoo your cat with a gentle, tear-free cleanser." and then writing an unrelated idea, "Your Persian is a cute and fluffy animal." shows incoherence in the manuscript. A writer's awareness of timelines in a paragraph also helps your readers to follow the paragraph thesis. Using past, present and future tenses correctly are essential for successful paragraph formation.
Correct grammar and spelling are critical structuring elements in a paragraph. Faulty spelling and grammar interfere with the reader's understanding of the main ideas. Use of slang, clichés and profane language also are detriments in paragraph structures. Choose words that are Standard English unless you are writing dialog for a fictional narrative. Use well-known and simpler words unless you are writing for an academic or other technical publication. Carefully chosen words help build reader comprehension and give organization for logical conclusions to your paragraphs.
Ending paragraphs with transitions to the next paragraphs is essential to the overall structure of a manuscript. The ending sentences in the paragraph should summarize the paragraph and give readers a quick preview of the next topic. A sentence such as "Grooming your cat is a daily aspect of pet ownership and a part of keeping your pet healthy on a daily basis" is, for example, a shift into the topic of cat health. Start the next paragraph with a related concept to the ending sentence of the last paragraph such as "While grooming is essential to your cat's health, be aware of medical conditions that can harm your pet." Transitions such as these will help your readers to understand the manuscript in an orderly way.