Perfect essays will be well planned. So build a plan on a paper before you start to write the essay. If you don't complete the essay, take account of your plan in what you turn in. You may get good marks. Good essays will be having a thesis (a provable argument) that is supported by data, argued through the use of fine paras. If you have no idea on what a perfect thesis is, you need to find it out right away. If you have no idea on what makes perfect proof in an argument, you need to find it right away. Excellent essays are put up on good paras. If you have no idea on how to write good paras, you need to be trained on it right away. All the paras in your essay should be linked to each other by middle words and phrases. If you have no idea what transitional words and phrases are, study about them before your exam. Good paras are built upon good sentences. If you have no idea on what a good sentence is, you need to be trained on it right away. Visit best essay writing service.
You may lose some marks for bad spelling, but you lose more marks for awful grammar. You may lose the most marks for bad formation as it makes the argument incomprehensible. A good well written essay will get more marks than a long poorly written essay. Here is the simple outline I studied in high school. It is around 600 words long. If the essay is longer than 600 words then you can use more supporting paras . Each para is about 100 words long. You can turn the 3 supporting paras into support parts with each part focusing on a picky kind of proof. There are changes, but they are most likely not needed at the high school stage.