Hey hopefulstudent,
I would agree that if you have more specific questions, you should feel free to ask away!
That said, however, I can link you to some tips and offer some general advice.
First, take a look at this:
Five Steps to Getting a 6 on Your GMAT Essays One of the most important tips? Pick a side and stick with it! The essay-graders (computer and human) want to see confidence. So don't waver!
Timing
In general, try to divide your time something like this:
First 3-5 minutes: Read the topic carefully and brainstorm on your scrap paper. Throw as many ideas as you can onto the paper for the first minute or so, then start narrowing down your main argument. Circle or write down the points that will support your thesis. This will serve as your outline and help you structure your essay.
Next 15-20 minutes: Write! Try to pace yourself, and be sure that each paragraph that follows your introduction relates to and supports your introduction and main idea.
Next 5 minutes: Proofread! Look out for grammatical errors and/or logical inconsistencies. Make any necessary changes.
Any additional time: Give yourself a second to stretch. Look away from the computer screen and blink a few times. Then, look over your essay again with "fresh" eyes. Look for proofreading errors again. Add in transition words between paragraphs if you don't have them already. Make sure your introduction, supporting paragraphs, and conclusion all work together. That said, DON'T try to completely change your essay... you don't want to run out of time! Make all the small changes you can, then call it a day.
Practice
It's pretty widely acknowledged that the AWA section is not quite as important as the GMAT Math and Verbal sections in the eyes of admissions committees. But that doesn't mean it doesn't matter and shouldn't be practiced prior to test day!
You should certainly try writing a number of practice essays before the test, with a timer and under test-like conditions. But even more important than that, perhaps, is
looking at sample essay prompts - both Analysis of an Argument and Analysis of an Issue. Give yourself 5 minutes to evaluate the prompt and craft a rough outline of what you would write about, were this topic to arise on test day. You'll find that most of the prompts have similar themes, and the more familiar you are with them, the less stressed out you'll be! This is an especially efficient way to prep if you're confident in your writing abilities but not necessarily in your ability to craft a strong argument.
Other Resources:
Sometimes it can be helpful to look at others' essays to see where they went wrong - and right!
A GMAT Essay Scored a Perfect 6 - with grading explanation
A GMAT Essay Scored a 5 - with explanation
A GMAT Essay Scored a 4 - with explanation
Good luck!
