Use the Right Keywords
Keywords are everything when it comes to online content, and that includes job postings. One of the main ways job seekers find jobs is through the search function, where they enter keywords pertaining to what they are looking for. If they are looking for an internship or entry level position, but you have not written that in your posting, they will not know it is a suitable job or it won't show up during a search. Think about keywords job seekers would use to find the type of job you are looking to fill.
Include the Details
Try to be as detailed and specific as possible in the job posting. The job seeker not only wants to know the title of the position, but as many details about their job requirements, schedule, and skills needed as possible. This lets them know if it is suitable for their experience, and helps you by getting applications and resumes from the most qualified people.
Try a Different Approach
Every once in a while, you will have a job posting that doesn't get a lot of exposure. This could be due to any number of things, so the best thing to do is change it up. Change the job posting title, how it is worded, add more or less details, or choose some different keywords. Still keep the information relevant to the position, but choose different ways of wording things. This can help you get it out to the right people using a job site such as Hound.
If you know this is a temporary, seasonal position, say so. Not only do you want as much exposure as possible, but you don't want to spend your time or the job seeker's time when they won't be able to commit to certain details about the position.