Add Guest Author Description using Custom Fields

Hello,

I recently followed WPBeginner.com’s tutorial on how to rewrite the author’s name as a guest author using custom fields. I would like to know how to do this for the author description? Currently the hack WPBeginner says to use works, but it still displays my description and username. What would I need to add to the functions to add a description in the custom fields? I’m a noob when it comes to custom fields.

Thanks!