Here is my guidance based on the job listing:

Tips For Applying

1. Demonstrate your teaching and assessment skills clearly: In my experience, having a diploma is just a base qualification. Highlighting the relevant experience you've obtained around lesson planning, conducting lessons and assessing students will boost your chances of securing the job.
2. Tailor your CV to match the job requirements: Mention any beauty therapy courses you have trained and results you have achieved therein. With my extensive experience in zimbabwean jobs recruitment, your CV carries a significant weight in selection process.
3. Include your achievements: Do not forget to include both academic and professional achievements that align with the job. It might be a certification in a specific beauty treatment method, or a commendable performance at a previous employment opportunity in Zimbabwe.
4. Showcase your relevant soft skills: pay attention to any soft skills mentioned implicitly, for instance, excellent communication skills, leadership, and interpersonal skills.
5. Follow application instruction: Apply via email as requested since it is quite an important element when scouting for job vacancies in Zimbabwe.

Areas to note

1. Qualifications and Experience: Applicants must have at least a diploma from a recognized institution. Having a higher educational qualification can be an added advantage.
2. Duties and Responsibilities: The duties stated are specific. A proper understanding and ability to delivery is pivotal.
3. Application Method: The only accepted application method is through email.
4. The job listing didn't mention a deadline but in my experience, I advise to apply as soon as you come across job vacancies in Zimbabwe as they tend to have numerous applicants.
5. The job listing didn't specifically provide a required experience level, however, in a competitive jobs market such as jobs in Zimbabwe that might be something important to consider.

Standing out in a crowded candidate pool

1. Show off certifications: What can set you apart from a sea of applicants is additional certifications that are relevant to the job.
2. Provide shining references: References from former employers or clients can offer a significant edge in a job search in Zimbabwe.
3. Customize your cover letter: A cover letter tailored to the specific role and company can make you outstanding. Show you've done your research and highlight how your skills align with their company values.

Things most applicants could miss

1. Application method: A common mistake novice applicants make is not following the job application method. It's clear here that applications should be sent via email.
2. Implicit skills: Many beginners will not read between the lines to identify implicit skills. Recount any experience you have in lesson planning, as this role involves that, too.
3. Addressing criteria indirectly: Even if you haven't directly trained beauty therapy courses previously, any experience where you have trained people or assessed competencies would be worth including.

In the realm of job vacancies in zim, the above points will make a significant difference in your application journey. Best of luck!