Changing Art Color and Background with Illustrator
When you have a file that is supposed to be white on black, but was sent black on white, changing the color is super simple.
Once you have your file open, hit Alt + 0 on PC or ⌘ + 0 on Mac to bring the artwork to front and center. Then hit Alt and + on PC or ⌘ and + on a mac to zoom in.
The easiest way to change a color is select it with the Magic Wand Tool. Select the Magic Wand and click on the color you would like to target.
The pink is to print white but was received pink so that you could see it on a white background. For a better visual reference we will make the background black, and pink white.
Before changing your image, first create a New Layer below your artwork, and draw a Black Box as a Background.
Now you can Lock your New Layer, and Magic Wand the color you would like to change. In your Color Window double click on the color which brings up a Color Picker Window where you can change the color with the slider.
Change to Pantone Color
If you would like to change the color to a Pantone you have to bring up the Pantone Swatch Book. Navigate to Window < Swatch Libraries < Color Books < PANTONE+ Solid Coated.
Once you have this open, you can Magic Wand the color you would like to change, and simply search the Pantone you would like to change to, and then Click on the Swatch to Change the Color.