1. Simple and clear title: The title is the first part that the recipient sees, so make sure it accurately conveys your theme and purpose. For example, if you are applying for a job in data analysis, you can set the title as "Data Analysis Job Application".

2. Introduce yourself: At the beginning of the email, briefly introduce yourself, including name, professional background, work experience, etc. This will help the recipient to know your basic information.

3. Show your professional ability: Describe your professional ability in detail, including your skills, knowledge and experience. For example, if you are a software engineer, you can list the programming languages you are familiar with and the projects you have completed. If you are a designer, you can show your design works and show your design process.

4. For example: Prove your professional ability and experience through specific examples. This can be a problem you solved in your previous work or a project you completed during your study.

5. Ending: At the end of the email, thank the recipient for his time and consideration, and express your desire for further communication.

6. Attachment: If necessary, a resume or portfolio can be attached. This will not only let the recipients know your professional ability more intuitively, but also save their time.

7. Language and format: Use professional language and format, and avoid using too colloquial or informal language. At the same time, keep your email clean and clear, so that the recipient can easily read and understand your email.