Create a party using the Party button. 

Then simply select "Custom Party" to create your own match. 

Here, you can customize every aspect of the game—choose the number of players, the number of rounds, and the type of rounds you want.
Options include Driving, Elimination, Stumble & Seek, Race, Challenges, Team modes, and more.
You can also enable or disable abilities, and choose to fill open player slots with AI Stumblers.

Note: Customized games do not grant rewards.

That’s a wrap on the social tour!