In this scenario, the footballer can primarily use Trademarks to show that the clothes are made by his company. Trademarks can protect brand names, logos, and slogans used in commerce, helping to distinguish his clothing line from those of other companies.
While Copyright may apply to some artistic designs or certain creative aspects of clothing, it is generally not used to indicate the source of goods. Registered designs can protect the visual appearance of the clothing, but they do not signify the origin. Patents are unlikely to be relevant unless the clothing incorporates a novel invention. Geographical indications are used to indicate the origin of goods and are typically relevant to specific products tied to a location, which doesn't apply here.
So, the best option for the footballer to represent his brand is Trademarks.