I think that if you have any previous work experience or volunteer work, put that somewhere really obvious on your resume. I know a lot of people list their qualities (eg. organised, reliable ect.) but if you can back that up with examples of times you have shown them (extracurriculars or past experience), that helps you stand out and builds credibility. Also, having a modern resume with a tasteful amount of colour and an organised and succinct layout makes the employer more likely to read it. Having good references is also v/ important (and not just your parents or relatives). A lot of teachers are happy to be your reference if you ask. If you've won any awards (like subject awards at school or external stuff like sporting achievements ect.) including them somewhere also helps to build your credibility.
The biggest thing is including things that are unique about you so that your application stands out. (Like if it's a job interacting with customers and you've done some sort of training through school about how to be a mentor/buddy, you can mention that as it's applicable. Likewise, if you are proficient in a second language then you can mention that. If it's a fast food job, you could mention the subject award you got for food tech ect.)