These three squares are, all, designed by the same designer. She made them in one colour, but, as you can see, the design allows you to do what you want. The patterns are charts, so you can easily follow them. they, all, are on Harry Potter world.
Squares Harry Potter
Knitted square in stranded work.
ID - Aiguilles magiques 2014
And... I saw that I used two different shades of blue when I wanted to make a photo of the Wimbourne Wasps square, too late.