If you use the site and gamble on sports and other things enough, you will receive points. Receive enough points, and you’ll get free spins for Lucky Wheel. The way it works is that the player in second place, receiving the silver trophy, gets 100 free spins of the Lucky Wheel. The person in third place receives the bronze trophy and 90 free spins, all the way down to 11th and 12th place where you receive 10 spins each.
These leaderboards and free spin wins are calculated per week, and all of this is located on the tournament board.
There’s also a promotion where you can get free spins every day by placing bets on whatever the game of the day is. For example, on Monday, the Game of the Day is Viking Gods: Thor and Loki.
These are going to vary from game to game, so your best bet is to check the actual game and promotion to make sure that you’ve done them all.