If it is the award-winning certificate of your related major or job-hunting activities, of course, it should be attached. It can be microfilmed on a page for people to see clearly and the size is moderate. Basically, A4 paper shall prevail. If it is smaller than A4 paper, copy it as it is. If it is larger than A4 paper, please reduce it to A4 paper size for recruiters to check. Also, for the awards of extracurricular activities, you can choose the most representative or weighty certificates, such as youth entrepreneurship knowledge contest, national/provincial XX ball contest, speech contest, outstanding young volunteers, etc., which can reflect your strengths and abilities.

Note that if it is something you think is cool, you may have different views on some conservative employers' awards, so you won't explain it, such as party queen, extreme sports, cosplay and so on.

Your letter had better have a cover, and if you have a recommendation letter from your tutor, it will certainly be the highlight. Explain your personal strengths and professional interests, your understanding of this company and position, and why you think you are suitable for this position.