How can I get access to the timer and change the color individually?

Your message seems to lack the code part…

You cannot change the color of hours and minutes independently, as there is a single subview.
If you do this

Code Block 
        for view in countDownTimer.subviews {
            view.setValue(UIColor.red, forKeyPath: "textColor")
        }

both will turn red, as there is a single subview.

You should use UIPickerView to customise more.
Read here:
https://stackoverflow.com/questions/37388633/how-to-customise-the-uidatepicker-components-in-swift