Legal basis: Article 19 of the National Flag Law of People's Republic of China (PRC) shall not display or use a damaged, defaced, faded or substandard national flag, or display or use the national flag upside down or in any other way that harms its dignity. Don't throw away the national flag at will. Damaged, defaced, faded or substandard national flags shall be recovered and disposed of in accordance with relevant state regulations. After the large-scale mass activities, the organizers of the activities shall take back or properly dispose of the national flag used at the event site. Article 20 The national flag and its patterns shall not be used as trademarks, patterns granted patent rights or commercial advertisements, and shall not be used in inappropriate occasions such as private funeral activities. Article 23 Whoever intentionally insults the people and the national flag of China by burning, damaging, scribbling, defileing or trampling in public places shall be investigated for criminal responsibility according to law; If the circumstances are relatively minor, the public security organ shall impose a detention of not more than fifteen days. Therefore, it is no problem to make it yourself and wear it yourself. If it is a commercial act, it may be illegal.