If you want to be a professional skateboarder someday, you should prepare yourself to be an independent contractor.
According to Jenkem Mag in their article about "16 things you didn't know about professional skateboarding," pro skaters are not employees. They said that professional skateboarders have to stay pretty versed in what they can write off for tax season.
Professional skateboarding careers have the same niche as pro wrestlers, MMA fighters, and other regular contractor professions like doctors, dentists, veterinarians, lawyers, etc.
The general rule is that an individual is an independent contractor if the payer has the right to control or direct only the result of the work and not what will be done and how it will be done.
Independent contractors must keep track of their earnings and include every client's payment. Clients are legally obliged to issue 1099-MISC forms to their contractors if the amount they paid warrants that expense.
Keeping receipt is crucial for being a pro skater since the average contract length for a professional skater depends on the company.
In addition, pro skaters must be comfortable filing their taxes quarterly with the IRS and paying for their insurance plus retirement savings because not all sponsorships provide it for the riders. For some, the freedom to choose sponsors, and the flexibility of working for other skate companies, make the challenges worth it.
Good luck with your endeavor, and always find the best skateboard manager for you to be in the right place.