The most ideal way to ensure parallel construction when writing an essay is to make sure to use a similar sentence structure from paragraph to paragraph. This means repeating a chosen form of grammar or grammatical structure within a sentence. When you employ the rule of making each paragraph in your essay follow the same grammatical pattern, you have succeeded in creating a parallel construction.
For example, “Mary likes to pick flowers, to play with butterflies, and to walk in the park” exhibits perfect parallelism, unlike “Mary likes to pick flowers, play with butterfly, and to walk in the park”.