How do I make color changing effects?

I want to make color changing sparkles and trails, so did SparkleColor.random() and Color.random(), but when I test the game, the colors don't change. Am I typing the code wrong? Please help!

here is the trail script:

function randomcolor()
    while true do
        script.Parent.Color = Color.Random()
        wait(1) 
    end
end
randomcolor()

here is the sparkle script:

function randomcolor()
    while true do
        script.Parent.SparkleColor = SparkleColor.Random()
        wait(1) 
    end
end
randomcolor()