Gemini
To dream that someone is a Gemini represents your quick thinking ability and keen wit. You are versatile and able to adapt to any situation. Alternatively, it signifies your connections and your ability (or inability) to reach out to others.
Colouring Book
To see or colour in a colouring book symbolises childhood. It indicates that you have a carefree attitude, free from any responsibilities. On the other hand, the dream may be warning you against being idle and wasting time on fruitless pursuits. Consider the significance of the colour you are using and what you are colouring. What is depicted in the colouring book suggests that you need to be more expressive in that area.
Santa Claus
To see Santa Claus in your dream indicates that you need to be more giving, accepting, and/or forgiving. You need to acknowledge and tend to some aspect of yourself. Alternatively, the dream means that you are reflecting on the good and bad things that you have done.
Doppelganger
To see your own doppelganger in your dream is a reflection of your negative actions. The dream is showing you the consequences of your actions and what you should not do. Alternatively, the dream signifies bad luck, danger, and/or illness.