Setting Custom Art

Custom Library Art

By default your non-steam games will have blank art. Just like the normal desktop version of Steam, you can use Steam in desktop mode to set custom art. You don't seem to be able to do this in gaming mode as of now.

It's definitely worth checking out https://www.steamgriddb.com/ to see if you game already has art for it.

You'll need two images, one for the icon and one for the banner.

Setting Custom Art

1. Enter Desktop mode
2. Click on the Steam icon on the taskbar, and select Library
3. In the Steam window, find and click on the game you wish to customize
4. Right-click (Left trigger) the banner at the top (the black box with the game's name on it)
5. In the context menu, select either Set Custom Background for the banner or Set Custom Logo for the icon
6. The file picker will be in the steam directory. To access your home directory, click on the blank rectangle with a dropdown arrow.
7. Click on the / select option that appears
8. Navigate to /home/deck and then find pictures in Desktop, Downloads, or Pictures. Wherever you put them.
9. Repeat for either the banner or the icon