What GUI system are you using? The built-in OnGUI or UGUI or..? Since you said "GUISkin", I'll take a stab at it being OnGUI. You can create a GUISkin asset and assign it to a public (or serializable) field in your script. Alternatively, if you only need styling for individual bits, you can declare public (or serializable) GUIStyles which are editable directly in the Inspector, and use those in your GUI calls. As a side note, this isn't the right section for that kind of question, as it's an implementation question rather than a design one.