What you will need is some food coloring - I used only two main colors, red and blue(and mixed them for purple). The frosting can be whipped cream or any other dense mixture which is preferably white or yellow. The one I used was with butter, whipped cream and powdered sugar. I divided it into 4 cups. In the first one I've put some red food coloring, second- blue, third 3drops red + 1 drop blue (to make purple) and the last cup I left pure ( so I have white color) To do the trick with 2colored icing it is important that you have either piping bag or frosting decoration press.When you have mixed all the frosting with the food coloring you pick two (or more) colors and start filling the bag/press one color at a time. When you apply it try to spread it only in one half of the bag. When you put the second colored frosting fill the gap that you left so it is equally divided in the bag. To finish the look add some sprinkles or any decoration you have!
Put a few spoons of sugar in the bag, then add 1 (or 2 drops) of food coloring in the bag. Hold it tight and shake a few times.And there you have your own fancy colored sugar. It is easy and it looks great!
Any questions are welcomed!