I first began with a 500×500 size document preset, set the foreground color to a shade of blue (I used #1680D1) and the background color to a dark blue (I used #0C1B6C). Create a new empty Layer (Shift + Ctrl + N (Mac: Shift + Command + N)), just above the default document background Layer. Activate that new empty Layer by selecting it in the Layers Palette. Next, select the ‘Gradient Tool (G)’ on