The footballer can use trademarks to show that the clothes are made by his company.
Trademarks are symbols, words, or phrases legally registered or established by use as representing a company or product. They can include logos, brand names, and other identifiers that can help consumers recognize the source of the goods. By registering a trademark, he can protect his brand and prevent others from using similar marks that could confuse consumers.
While other forms of intellectual property like patents (for inventions), geographical indications (for products from specific regions), copyright (for creative works), and registered designs (for the appearance of products) may also be relevant in different contexts, trademarks are specifically aimed at brand identification and consumer recognition, making them the most appropriate choice for this scenario.