To change a Board Background, you first need to navigate to the "View boards" button in the bottom left-hand corner of your Space.
From there, hover over the board for which you want to change the background, and click on the 3 dots.
When you've clicked the 3 dots, another menu should appear that looks like the one below. Click on the "Change background" button from here to access the other Board Background options.
After clicking this button, another pop-up will appear. You can choose to change your Board Background to a pattern, or a color. Once you've picked a new background, you can choose to set the background as a default for all new boards in the Space, and then click the blue "Confirm" button in the bottom right-hand corner of the pop-up.
Then, your Board Background will be changed to whatever you've selected!
