If you're not familiar with RICE, please read this article about different approaches to feature prioritization.
To get started with RICE prioritization head over to the Prioritization page.
Give your board a name.
Add some features to the board.
Click on the gear button to configure all of the prioritization settings for your board.
Below is the default list of factors for the RICE board, you can configure additional impact factors as you please.
Here's an example of a non-default prioritization configuration: