When only a fragment of a dream is recalled it can be difficult for someone other than the dreamer to elucidate its meaning. Dream symbols are best understood by looking at their relationship to the other symbols, events and feelings in the dream. Think of a dream as a completed jigsaw puzzle and a symbol as one piece of that puzzle. Viewed alone the piece gives you very little, if any, insight into the meaning of the whole picture.
But you, the dreamer, do know, deep in your unconscious mind, the meaning of each symbol in your dream, so the key to understanding a single symbol is to ask your unconscious mind. One of the best ways to do this is to dialogue with the symbol. I have suggested a dialogue dream alchemy practise for you.
You have given a strong clue though! You have had two dreams, the first version showing a scalp, the second a skull cap. When a dream theme repeats it is interesting to note any changes as these indicate how you are progressing or regressing with the issue. Your blue colour has moved from the skin of the head further out into the world in the form of a cap.
Sometimes the head, in dreams, represents thinking or conditioned thoughts. Since hair grows from the head, it may represent ideas, which also come from the head. What we do with hair in dreams (colour, style and so on) sometimes reflects how we are utilising and expressing our ideas.
In your dream there are wisps of hair in the first dream. Perhaps these are the beginnings of new ideas following a period of baldness – of lack of creative ideas. Wisps of hair could be the leftovers after the balding process but the glowing iridescence of the skull in your dream suggests more vitality. Perhaps the second dream reflects what you can manifest from your ideas. Not a skull cap, but something physical, the materialisation of an idea.
When you look at the colour blue, what feeling does it give you? What does it remind you of? Do your answers remind you of a situation in your life today?
Consult me confidentially about your dream.

Dialogue
Your dialogue is between a yourself and the blue skull cap. Start with you saying, “What kind of person wears a blue skull cap like you?” and see what the skull cap automatically answers. Keep it going for 20 minutes.
How to do this
Give yourself no longer than 20 minutes. When you do this exercise do NOT think! Don’t plan ahead. Just let whatever happens happen. Let the two entities speak to each other on paper using whatever words come up. It’s a bit like writing a film script or play – but without the brain being involved.
How does this work?
By not thinking, by keeping the words flowing, you are letting your right brain and unconscious mind do most of the work. They created the original dream so they know what these symbols mean for you. They will reveal. You will be surprised.
More details on Dialogue as a Dream Alchemy Practice in: “Dream Alchemy” by Jane Teresa Anderson, pages 321-4 and 333.
Jane Teresa Anderson