You will need to finish episode 5 before you can start creating your own game.
Within your game, you need to think about the person playing your game:
- is the game too easy?
- is the game too repetitive?
- does it take any skill to win the game?
- does the game make your player have to try different scenarios?
Think about your game as anyone would who creates mario, minecraft or any other video game. Why would someone want to buy your game?