This article ONLY applies if you already have a Box account!
To login to Box, go to https://csuchico.app.box.com/
You should see the screen below. Click "Continue".
On the next screen, enter your Chico login credentials (including "@csuchico.edu"), and click Next. You will be prompted for Duo.
Enter your password. Click Sign in.
Once logged in, you should see your Box home screen, with all the folders and files you have access to.