Once you've chosen a topic and decided on an approach and structure for your college admissions essay, it's time to write. And since this is probably the most important essay you've ever written, you'll want to make sure that your writing is excellent. That means no mistakes, of course, but it also means writing in a readable style and presenting yourself as a mature and capable writer.

Here are some essay writing tips to consider when putting together your college admissions essay:

Your grammar, usage, and mechanics must be perfect.

When you write your college admissions essay, there cannot be any mistakes. Mistakes include not only misused punctuation, but also poor subject-verb agreement, dangling participles, and other more subtle issues.

Most high school seniors haven't entirely mastered the grammar rules, and that's OK. But that doesn't mean it's OK to have mistakes in your essay. (Some people will disagree with this, but it makes no sense to have imperfect grammar if you can avoid it). After you've screened your essay for any grammar mistakes, find someone with a perfect command of the English language to look over your final draft and point out any remaining issues, providing some additional essay writing tips.

Be mindful of your vocabulary.

Speaking intelligently is important. But many applicants get in trouble by trying to use too many big words. Admissions officers roll their eyes when they see a high school student use a word that either doesn't quite fit or replaces a smaller word that would work just as well. Speak plainly, and focus more on which words you choose than how long they are.

Use an active voice.

This is an important essay writing tip. Good writing uses the active voice and avoids the passive one. Passive writing bores the reader, while active writing stimulates the imagination and lends a greater sense of immediacy to your writing.

An example:

Passive voice: Football is the sport that I play.

Active voice: I play football.

Passive writing can be hard to catch, and while some of it is OK too much can ruin an essay. Go through your essay one sentence at a time to check active vs. passive voice.

Vary sentence length.

One thing that makes writing more enjoyable to read is a variety of sentence types and lengths. Don't use all long sentences or all short ones. Mix it up.

Use gender-neutral language.

Don't use the male pronoun when it's not appropriate.

For example, you can't say "I don't know who my doctor will be, but I hope he's good." You also can't replace "he" with "they," because "they" is plural and you're talking here about one doctor. For this sentence, you'd want to say "...I hope he or she is good."

Write in an appropriate style.

An admissions essay should feel conversational and intimate. This isn't a paper about Greek mythology or the theory of relativity. It should draw the reader in with a style that is comfortable and gives the reader a sense of your personality and how you typically write and talk.

However, you don't want to be too casual. Don't use slang ("diss" and "dude" are inappropriate!) Don't curse. Don't abbreviate words.

Sarcasm can sometimes be difficult to detect in writing and can backfire. The same goes for humor, which should only be included if you're sure that it works and it doesn't overwhelm the essay.