It's often the content of a job posting that determines the quantity and quality of the applicants it receives. The first thing to consider when writing a job post is the title of the position, since this will be the first thing that anyone sees of the job. We highly recommend keeping job titles concise. Make sure to include accurate reflections of the position that you want to fill.
Naming a position "GUARANTEED BEST COMMISSION IN THE STATE!!" may grab some attention, but it ultimately says nothing about the job itself, meaning that many qualified candidates might pass over it in favor of job postings that show the position title up-front.
Similarly, if the position title listed in your job posting doesn't actually contain the name of the position, it will be much more difficult for someone to search for. In the example above, if a jobseeker were to search the phrase "sales," that posting probably won't show up in the results since it isn't being listed as a "Sales Representative" position.
Job Description should be an overview of what an applicant can expect of the job--this would likely include the duties associated with the position, the schedule, and any benefits that are offered by the company for this position.
Job Requirements should include any specific criteria that an applicant must meet before applying for the job. This might include something like "Must be over 18 years old" or "At least 3 years of experience with plumbing."
Job Preferences are additional criteria that aren't mandatory, but should still be considered by applicants. Something like "Associate's Degree preferred" would be appropriate here.
Company Culture is an optional field where you would describe the company as a whole, rather than the specific position. An example of a brief company culture description would be "We are a fast-paced, customer-oriented workplace with a high emphasis on open communication and employee satisfaction."
You can also optionally set an expiration date for your job if you would like it automatically taken down on a certain date.
To learn more about how to post a job, see How do I post a job?