Coin Master shares daily free spins and coins reward links on the game’s social media pages.
These free spins link created and shared by game creators. It means, you can not create such links to get free spins.
In the market, if you found such sources who claim that they generate such links, then it is suggested to stay away from such sources.
Now, how to get these links? Answer is simple, follow Coin Master social media pages and follow fan base blogs who list such links in a single page.